[EME] Update content_decryption_module.h to more recent revision

Adds support for cdm::ContentDecryptionModule_9 and cdm::Host_9 definitions, HDCP definitions, and 10 and 12 bit image format definitions.

4 files changed, 193 insertions, 103 deletions

diff --git a/dom/media/gmp/widevine-adapter/WidevineAdapter.cpp b/dom/media/gmp/widevine-adapter/WidevineAdapter.cpp
index fa703ab0b8..57d4ecec27 100644
--- a/dom/media/gmp/widevine-adapter/WidevineAdapter.cpp
+++ b/dom/media/gmp/widevine-adapter/WidevineAdapter.cpp
@@ -106,8 +106,8 @@ WidevineAdapter::GMPGetAPI(const char* aAPIName,
 
     WidevineDecryptor* decryptor = new WidevineDecryptor();
 
-    auto cdm = reinterpret_cast<cdm::ContentDecryptionModule*>(
-      create(cdm::ContentDecryptionModule::kVersion,
+    auto cdm = reinterpret_cast<cdm::ContentDecryptionModule_9*>(
+      create(cdm::ContentDecryptionModule_9::kVersion,
              kEMEKeySystemWidevine.get(),
              kEMEKeySystemWidevine.Length(),
              &GetCdmHost,
@@ -161,7 +161,7 @@ WidevineAdapter::Supports(int32_t aModuleVersion,
                           int32_t aHostVersion)
 {
   return aModuleVersion == CDM_MODULE_VERSION &&
-         aInterfaceVersion == cdm::ContentDecryptionModule::kVersion &&
+         aInterfaceVersion == cdm::ContentDecryptionModule_9::kVersion &&
          aHostVersion == cdm::Host_9::kVersion;
 }
 
diff --git a/dom/media/gmp/widevine-adapter/WidevineUtils.cpp b/dom/media/gmp/widevine-adapter/WidevineUtils.cpp
index deb71e51a5..10c6c2e18c 100644
--- a/dom/media/gmp/widevine-adapter/WidevineUtils.cpp
+++ b/dom/media/gmp/widevine-adapter/WidevineUtils.cpp
@@ -43,7 +43,7 @@ ToGMPErr(cdm::Status aStatus)
     case cdm::kSuccess: return GMPNoErr;
     case cdm::kNeedMoreData: return GMPGenericErr;
     case cdm::kNoKey: return GMPNoKeyErr;
-    case cdm::kSessionError: return GMPGenericErr;
+    case cdm::kInitializationError: return GMPGenericErr;
     case cdm::kDecryptError: return GMPCryptoErr;
     case cdm::kDecodeError: return GMPDecodeErr;
     case cdm::kDeferredInitialization: return GMPGenericErr;
diff --git a/dom/media/gmp/widevine-adapter/content_decryption_module.h b/dom/media/gmp/widevine-adapter/content_decryption_module.h
index 512ca97689..3f065017bf 100644
--- a/dom/media/gmp/widevine-adapter/content_decryption_module.h
+++ b/dom/media/gmp/widevine-adapter/content_decryption_module.h
@@ -5,6 +5,8 @@
 #ifndef CDM_CONTENT_DECRYPTION_MODULE_H_
 #define CDM_CONTENT_DECRYPTION_MODULE_H_
 
+#include "content_decryption_module_export.h"
+
 #if defined(_MSC_VER)
 typedef unsigned char uint8_t;
 typedef unsigned int uint32_t;
@@ -14,25 +16,21 @@ typedef __int64 int64_t;
 #include <stdint.h>
 #endif
 
-// Define CDM_EXPORT so that functionality implemented by the CDM module
-// can be exported to consumers.
-#if defined(WIN32)
-
-#if defined(CDM_IMPLEMENTATION)
-#define CDM_EXPORT __declspec(dllexport)
-#else
-#define CDM_EXPORT __declspec(dllimport)
-#endif  // defined(CDM_IMPLEMENTATION)
-
-#else  // defined(WIN32)
-
-#if defined(CDM_IMPLEMENTATION)
-#define CDM_EXPORT __attribute__((visibility("default")))
+// Define CDM_CLASS_API to export class types. We have to add visibility
+// attributes to make sure virtual tables in CDM consumer and CDM implementation
+// are the same. Generally, it was always a good idea, as there're no guarantees
+// about that for the internal symbols, but it has only become a practical issue
+// after introduction of LTO devirtualization. See more details on
+// https://crbug.com/609564#c35
+#if defined(_WIN32)
+#if defined(__clang__)
+#define CDM_CLASS_API [[clang::lto_visibility_public]]
 #else
-#define CDM_EXPORT
+#define CDM_CLASS_API
 #endif
-
-#endif  // defined(WIN32)
+#else  // defined(_WIN32)
+#define CDM_CLASS_API __attribute__((visibility("default")))
+#endif  // defined(_WIN32)
 
 // The version number must be rolled when the exported functions are updated!
 // If the CDM and the adapter use different versions of these functions, the
@@ -48,9 +46,9 @@ typedef __int64 int64_t;
 #define BUILD_ENTRYPOINT_NO_EXPANSION(name, version) name##_##version
 
 extern "C" {
-CDM_EXPORT void INITIALIZE_CDM_MODULE();
+CDM_API void INITIALIZE_CDM_MODULE();
 
-CDM_EXPORT void DeinitializeCdmModule();
+CDM_API void DeinitializeCdmModule();
 
 // Returns a pointer to the requested CDM Host interface upon success.
 // Returns NULL if the requested CDM Host interface is not supported.
@@ -65,30 +63,30 @@ typedef void* (*GetCdmHostFunc)(int host_interface_version, void* user_data);
 // |cdm_interface_version|.
 // Caller retains ownership of arguments and must call Destroy() on the returned
 // object.
-CDM_EXPORT void* CreateCdmInstance(
+CDM_API void* CreateCdmInstance(
     int cdm_interface_version,
     const char* key_system, uint32_t key_system_size,
     GetCdmHostFunc get_cdm_host_func, void* user_data);
 
-CDM_EXPORT const char* GetCdmVersion();
+CDM_API const char* GetCdmVersion();
 }
 
 namespace cdm {
 
-class AudioFrames;
-class DecryptedBlock;
-class VideoFrame;
+class CDM_CLASS_API AudioFrames;
+class CDM_CLASS_API DecryptedBlock;
+class CDM_CLASS_API VideoFrame;
 
-class Host_7;
-class Host_8;
+class CDM_CLASS_API Host_8;
+class CDM_CLASS_API Host_9;
 
 enum Status {
   kSuccess = 0,
   kNeedMoreData,  // Decoder needs more data to produce a decoded frame/sample.
-  kNoKey,  // The required decryption key is not available.
-  kSessionError,  // Session management error.
-  kDecryptError,  // Decryption failed.
-  kDecodeError,  // Error decoding audio or video.
+  kNoKey,         // The required decryption key is not available.
+  kInitializationError,    // Initialization error.
+  kDecryptError,           // Decryption failed.
+  kDecodeError,            // Error decoding audio or video.
   kDeferredInitialization  // Decoder is not ready for initialization.
 };
 
@@ -97,6 +95,7 @@ enum Status {
 // The following starts with the list of DOM4 exceptions from:
 // http://www.w3.org/TR/dom/#domexception
 // Some DOM4 exceptions are not included as they are not expected to be used.
+// Should only be used on Host_8 and before.
 enum Error {
   kNotSupportedError = 9,
   kInvalidStateError = 11,
@@ -113,8 +112,20 @@ enum Error {
   kOutputError = 101
 };
 
-// Time is defined as the number of seconds since the
-// Epoch (00:00:00 UTC, January 1, 1970).
+// Exceptions used by the CDM to reject promises.
+// https://w3c.github.io/encrypted-media/#exceptions
+enum Exception {
+  kExceptionTypeError,
+  kExceptionNotSupportedError,
+  kExceptionInvalidStateError,
+  kExceptionQuotaExceededError
+};
+
+// Time is defined as the number of seconds since the Epoch
+// (00:00:00 UTC, January 1, 1970), not including any added leap second.
+// Also see Time definition in spec: https://w3c.github.io/encrypted-media/#time
+// Note that Time is defined in millisecond accuracy in the spec but in second
+// accuracy here.
 typedef double Time;
 
 // An input buffer can be split into several continuous subsamples.
@@ -151,13 +162,13 @@ struct SubsampleEntry {
 // unencrypted.
 struct InputBuffer {
   InputBuffer()
-      : data(NULL),
+      : data(nullptr),
         data_size(0),
-        key_id(NULL),
+        key_id(nullptr),
         key_id_size(0),
-        iv(NULL),
+        iv(nullptr),
         iv_size(0),
-        subsamples(NULL),
+        subsamples(nullptr),
         num_subsamples(0),
         timestamp(0) {}
 
@@ -188,7 +199,7 @@ struct AudioDecoderConfig {
         channel_count(0),
         bits_per_channel(0),
         samples_per_second(0),
-        extra_data(NULL),
+        extra_data(nullptr),
         extra_data_size(0) {}
 
   AudioCodec codec;
@@ -214,10 +225,25 @@ enum AudioFormat {
 };
 
 // Surface formats based on FOURCC labels, see: http://www.fourcc.org/yuv.php
+// Values are chosen to be consistent with Chromium's VideoPixelFormat values.
 enum VideoFormat {
   kUnknownVideoFormat = 0,  // Unknown format value. Used for error reporting.
-  kYv12,  // 12bpp YVU planar 1x1 Y, 2x2 VU samples.
-  kI420  // 12bpp YVU planar 1x1 Y, 2x2 UV samples.
+  kYv12 = 1,                // 12bpp YVU planar 1x1 Y, 2x2 VU samples.
+  kI420 = 2,                // 12bpp YUV planar 1x1 Y, 2x2 UV samples.
+
+  // In the following formats, each sample uses 16-bit in storage, while the
+  // sample value is stored in the least significant N bits where N is
+  // specified by the number after "P". For example, for YUV420P9, each Y, U,
+  // and V sample is stored in the least significant 9 bits in a 2-byte block.
+  kYUV420P9 = 16,
+  kYUV420P10 = 17,
+  kYUV422P9 = 18,
+  kYUV422P10 = 19,
+  kYUV444P9 = 20,
+  kYUV444P10 = 21,
+  kYUV420P12 = 22,
+  kYUV422P12 = 23,
+  kYUV444P12 = 24,
 };
 
 struct Size {
@@ -245,14 +271,19 @@ struct VideoDecoderConfig {
     kH264ProfileHigh,
     kH264ProfileHigh10,
     kH264ProfileHigh422,
-    kH264ProfileHigh444Predictive
+    kH264ProfileHigh444Predictive,
+    // VP9 Profiles are only passed in starting from CDM_9.
+    kVP9Profile0,
+    kVP9Profile1,
+    kVP9Profile2,
+    kVP9Profile3
   };
 
   VideoDecoderConfig()
       : codec(kUnknownVideoCodec),
         profile(kUnknownVideoCodecProfile),
         format(kUnknownVideoFormat),
-        extra_data(NULL),
+        extra_data(nullptr),
         extra_data_size(0) {}
 
   VideoCodec codec;
@@ -294,7 +325,7 @@ struct PlatformChallengeResponse {
 
 // Used when passing arrays of binary data. Does not own the referenced data.
 struct BinaryData {
-  BinaryData() : data(NULL), length(0) {}
+  BinaryData() : data(nullptr), length(0) {}
   const uint8_t* data;
   uint32_t length;
 };
@@ -316,7 +347,10 @@ enum KeyStatus {
 // should be 0 when |status| == kUsable.
 struct KeyInformation {
   KeyInformation()
-      : key_id(NULL), key_id_size(0), status(kInternalError), system_code(0) {}
+      : key_id(nullptr),
+        key_id_size(0),
+        status(kInternalError),
+        system_code(0) {}
   const uint8_t* key_id;
   uint32_t key_id_size;
   KeyStatus status;
@@ -372,6 +406,24 @@ enum MessageType {
   kLicenseRelease = 2
 };
 
+enum HdcpVersion {
+  kHdcpVersionNone,
+  kHdcpVersion1_0,
+  kHdcpVersion1_1,
+  kHdcpVersion1_2,
+  kHdcpVersion1_3,
+  kHdcpVersion1_4,
+  kHdcpVersion2_0,
+  kHdcpVersion2_1,
+  kHdcpVersion2_2
+};
+
+struct Policy {
+  Policy() : min_hdcp_version(kHdcpVersionNone) {}
+
+  HdcpVersion min_hdcp_version;
+};
+
 // FileIO interface provides a way for the CDM to store data in a file in
 // persistent storage. This interface aims only at providing basic read/write
 // capabilities and should not be used as a full fledged file IO API.
@@ -381,7 +433,7 @@ enum MessageType {
 // Note to implementors of this interface:
 // Per-origin storage and the ability for users to clear it are important.
 // See http://www.w3.org/TR/encrypted-media/#privacy-storedinfo.
-class FileIO {
+class CDM_CLASS_API FileIO {
  public:
   // Opens the file with |file_name| for read and write.
   // FileIOClient::OnOpenComplete() will be called after the opening
@@ -421,7 +473,7 @@ class FileIO {
 // When kError is returned, the FileIO object could be in an error state. All
 // following calls (other than Close()) could return kError. The CDM should
 // still call Close() to destroy the FileIO object.
-class FileIOClient {
+class CDM_CLASS_API FileIOClient {
  public:
   enum Status {
     kSuccess = 0,
@@ -462,10 +514,20 @@ class FileIOClient {
 // provided in CreateCdmInstance() to allocate any Buffer that needs to
 // be passed back to the caller. Implementations must call Buffer::Destroy()
 // when a Buffer is created that will never be returned to the caller.
-class ContentDecryptionModule_7 {
+class CDM_CLASS_API ContentDecryptionModule_8 {
  public:
-  static const int kVersion = 7;
-  typedef Host_7 Host;
+  static const int kVersion = 8;
+  typedef Host_8 Host;
+
+  // Initializes the CDM instance, providing information about permitted
+  // functionalities.
+  // If |allow_distinctive_identifier| is false, messages from the CDM,
+  // such as message events, must not contain a Distinctive Identifier,
+  // even in an encrypted form.
+  // If |allow_persistent_state| is false, the CDM must not attempt to
+  // persist state. Calls to CreateFileIO() will fail.
+  virtual void Initialize(bool allow_distinctive_identifier,
+                          bool allow_persistent_state) = 0;
 
   // SetServerCertificate(), CreateSessionAndGenerateRequest(), LoadSession(),
   // UpdateSession(), CloseSession(), and RemoveSession() all accept a
@@ -484,8 +546,7 @@ class ContentDecryptionModule_7 {
   // or Host::OnRejectPromise().
   virtual void CreateSessionAndGenerateRequest(uint32_t promise_id,
                                                SessionType session_type,
-                                               const char* init_data_type,
-                                               uint32_t init_data_type_size,
+                                               InitDataType init_data_type,
                                                const uint8_t* init_data,
                                                uint32_t init_data_size) = 0;
 
@@ -631,8 +692,8 @@ class ContentDecryptionModule_7 {
   virtual void Destroy() = 0;
 
  protected:
-  ContentDecryptionModule_7() {}
-  virtual ~ContentDecryptionModule_7() {}
+  ContentDecryptionModule_8() {}
+  virtual ~ContentDecryptionModule_8() {}
 };
 
 // ContentDecryptionModule interface that all CDMs need to implement.
@@ -641,10 +702,10 @@ class ContentDecryptionModule_7 {
 // provided in CreateCdmInstance() to allocate any Buffer that needs to
 // be passed back to the caller. Implementations must call Buffer::Destroy()
 // when a Buffer is created that will never be returned to the caller.
-class ContentDecryptionModule_8 {
+class CDM_CLASS_API ContentDecryptionModule_9 {
  public:
-  static const int kVersion = 8;
-  typedef Host_8 Host;
+  static const int kVersion = 9;
+  typedef Host_9 Host;
 
   // Initializes the CDM instance, providing information about permitted
   // functionalities.
@@ -656,6 +717,13 @@ class ContentDecryptionModule_8 {
   virtual void Initialize(bool allow_distinctive_identifier,
                           bool allow_persistent_state) = 0;
 
+  // Gets the key status if the CDM has a hypothetical key with the |policy|.
+  // The CDM must respond by calling either Host::OnResolveKeyStatusPromise()
+  // with the result key status or Host::OnRejectPromise() if an unexpected
+  // error happened or this method is not supported.
+  virtual void GetStatusForPolicy(uint32_t promise_id,
+                                  const Policy& policy) = 0;
+
   // SetServerCertificate(), CreateSessionAndGenerateRequest(), LoadSession(),
   // UpdateSession(), CloseSession(), and RemoveSession() all accept a
   // |promise_id|, which must be passed to the completion Host method
@@ -815,18 +883,23 @@ class ContentDecryptionModule_8 {
       uint32_t link_mask,
       uint32_t output_protection_mask) = 0;
 
+  // Called by the host after a call to Host::RequestStorageId(). If the storage
+  // ID is not available, null/zero will be provided.
+  virtual void OnStorageId(const uint8_t* storage_id,
+                           uint32_t storage_id_size) = 0;
+
   // Destroys the object in the same context as it was created.
   virtual void Destroy() = 0;
 
  protected:
-  ContentDecryptionModule_8() {}
-  virtual ~ContentDecryptionModule_8() {}
+  ContentDecryptionModule_9() {}
+  virtual ~ContentDecryptionModule_9() {}
 };
 
-typedef ContentDecryptionModule_8 ContentDecryptionModule;
+typedef ContentDecryptionModule_9 ContentDecryptionModule;
 
 // Represents a buffer created by Allocator implementations.
-class Buffer {
+class CDM_CLASS_API Buffer {
  public:
   // Destroys the buffer in the same context as it was created.
   virtual void Destroy() = 0;
@@ -845,9 +918,9 @@ class Buffer {
   void operator=(const Buffer&);
 };
 
-class Host_7 {
+class CDM_CLASS_API Host_8 {
  public:
-  static const int kVersion = 7;
+  static const int kVersion = 8;
 
   // Returns a Buffer* containing non-zero members upon success, or NULL on
   // failure. The caller owns the Buffer* after this call. The buffer is not
@@ -859,7 +932,7 @@ class Host_7 {
   // from now with |context|.
   virtual void SetTimer(int64_t delay_ms, void* context) = 0;
 
-  // Returns the current wall time in seconds.
+  // Returns the current wall time.
   virtual Time GetCurrentWallTime() = 0;
 
   // Called by the CDM when a session is created or loaded and the value for the
@@ -917,8 +990,10 @@ class Host_7 {
   // session |session_id|. This can happen as the result of an Update() call
   // or some other event. If this happens as a result of a call to Update(),
   // it must be called before resolving the Update() promise. |new_expiry_time|
-  // can be 0 to represent "undefined". Size parameter should not include
-  // null termination.
+  // represents the time after which the key(s) in the session will no longer
+  // be usable for decryption. It can be 0 if no such time exists or if the
+  // license explicitly never expires. Size parameter should not include null
+  // termination.
   virtual void OnExpirationChange(const char* session_id,
                                   uint32_t session_id_size,
                                   Time new_expiry_time) = 0;
@@ -978,13 +1053,13 @@ class Host_7 {
   virtual FileIO* CreateFileIO(FileIOClient* client) = 0;
 
  protected:
-  Host_7() {}
-  virtual ~Host_7() {}
+  Host_8() {}
+  virtual ~Host_8() {}
 };
 
-class Host_8 {
+class CDM_CLASS_API Host_9 {
  public:
-  static const int kVersion = 8;
+  static const int kVersion = 9;
 
   // Returns a Buffer* containing non-zero members upon success, or NULL on
   // failure. The caller owns the Buffer* after this call. The buffer is not
@@ -996,9 +1071,14 @@ class Host_8 {
   // from now with |context|.
   virtual void SetTimer(int64_t delay_ms, void* context) = 0;
 
-  // Returns the current wall time in seconds.
+  // Returns the current wall time.
   virtual Time GetCurrentWallTime() = 0;
 
+  // Called by the CDM when a key status is available in response to
+  // GetStatusForPolicy().
+  virtual void OnResolveKeyStatusPromise(uint32_t promise_id,
+                                         KeyStatus key_status) = 0;
+
   // Called by the CDM when a session is created or loaded and the value for the
   // MediaKeySession's sessionId attribute is available (|session_id|).
   // This must be called before OnSessionMessage() or
@@ -1016,26 +1096,21 @@ class Host_8 {
 
   // Called by the CDM when an error occurs as a result of one of the
   // ContentDecryptionModule calls that accept a |promise_id|.
-  // |error| must be specified, |error_message| and |system_code|
+  // |exception| must be specified. |error_message| and |system_code|
   // are optional. |error_message_size| should not include null termination.
   virtual void OnRejectPromise(uint32_t promise_id,
-                               Error error,
+                               Exception exception,
                                uint32_t system_code,
                                const char* error_message,
                                uint32_t error_message_size) = 0;
 
   // Called by the CDM when it has a message for session |session_id|.
   // Size parameters should not include null termination.
-  // |legacy_destination_url| is only for supporting the prefixed EME API and
-  // is ignored by unprefixed EME. It should only be non-null if |message_type|
-  // is kLicenseRenewal.
   virtual void OnSessionMessage(const char* session_id,
                                 uint32_t session_id_size,
                                 MessageType message_type,
                                 const char* message,
-                                uint32_t message_size,
-                                const char* legacy_destination_url,
-                                uint32_t legacy_destination_url_length) = 0;
+                                uint32_t message_size) = 0;
 
   // Called by the CDM when there has been a change in keys or their status for
   // session |session_id|. |has_additional_usable_key| should be set if a
@@ -1054,8 +1129,10 @@ class Host_8 {
   // session |session_id|. This can happen as the result of an Update() call
   // or some other event. If this happens as a result of a call to Update(),
   // it must be called before resolving the Update() promise. |new_expiry_time|
-  // can be 0 to represent "undefined". Size parameter should not include
-  // null termination.
+  // represents the time after which the key(s) in the session will no longer
+  // be usable for decryption. It can be 0 if no such time exists or if the
+  // license explicitly never expires. Size parameter should not include null
+  // termination.
   virtual void OnExpirationChange(const char* session_id,
                                   uint32_t session_id_size,
                                   Time new_expiry_time) = 0;
@@ -1065,21 +1142,6 @@ class Host_8 {
   virtual void OnSessionClosed(const char* session_id,
                                uint32_t session_id_size) = 0;
 
-  // Called by the CDM when an error occurs in session |session_id|
-  // unrelated to one of the ContentDecryptionModule calls that accept a
-  // |promise_id|. |error| must be specified, |error_message| and
-  // |system_code| are optional. Length parameters should not include null
-  // termination.
-  // Note:
-  // - This method is only for supporting prefixed EME API.
-  // - This method will be ignored by unprefixed EME. All errors reported
-  //   in this method should probably also be reported by one of other methods.
-  virtual void OnLegacySessionError(
-      const char* session_id, uint32_t session_id_length,
-      Error error,
-      uint32_t system_code,
-      const char* error_message, uint32_t error_message_length) = 0;
-
   // The following are optional methods that may not be implemented on all
   // platforms.
 
@@ -1114,13 +1176,19 @@ class Host_8 {
   // CDM can call this method multiple times to operate on different files.
   virtual FileIO* CreateFileIO(FileIOClient* client) = 0;
 
+  // Requests the storage ID. The ID will be returned by the host via
+  // ContentDecryptionModule::OnStorageId(). A storage ID is a stable, device
+  // specific ID used by the CDM to securely store persistent data. The CDM must
+  // not expose the ID outside the client device, even in encrypted form.
+  virtual void RequestStorageId() = 0;
+
  protected:
-  Host_8() {}
-  virtual ~Host_8() {}
+  Host_9() {}
+  virtual ~Host_9() {}
 };
 
 // Represents a decrypted block that has not been decoded.
-class DecryptedBlock {
+class CDM_CLASS_API DecryptedBlock {
  public:
   virtual void SetDecryptedBuffer(Buffer* buffer) = 0;
   virtual Buffer* DecryptedBuffer() = 0;
@@ -1135,7 +1203,7 @@ class DecryptedBlock {
   virtual ~DecryptedBlock() {}
 };
 
-class VideoFrame {
+class CDM_CLASS_API VideoFrame {
  public:
   enum VideoPlane {
     kYPlane = 0,
@@ -1178,7 +1246,7 @@ class VideoFrame {
 //
 // |<----------------- AudioFrames ------------------>|
 // | audio buffer 0 | audio buffer 1 | audio buffer 2 |
-class AudioFrames {
+class CDM_CLASS_API AudioFrames {
  public:
   virtual void SetFrameBuffer(Buffer* buffer) = 0;
   virtual Buffer* FrameBuffer() = 0;
diff --git a/dom/media/gmp/widevine-adapter/content_decryption_module_export.h b/dom/media/gmp/widevine-adapter/content_decryption_module_export.h
new file mode 100644
index 0000000000..51d485892b
--- /dev/null
+++ b/dom/media/gmp/widevine-adapter/content_decryption_module_export.h
@@ -0,0 +1,22 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CDM_CONTENT_DECRYPTION_MODULE_EXPORT_H_
+#define CDM_CONTENT_DECRYPTION_MODULE_EXPORT_H_
+
+// Define CDM_API so that functionality implemented by the CDM module
+// can be exported to consumers.
+#if defined(_WIN32)
+
+#if defined(CDM_IMPLEMENTATION)
+#define CDM_API __declspec(dllexport)
+#else
+#define CDM_API __declspec(dllimport)
+#endif  // defined(CDM_IMPLEMENTATION)
+
+#else  // defined(_WIN32)
+#define CDM_API __attribute__((visibility("default")))
+#endif  // defined(_WIN32)
+
+#endif  // CDM_CONTENT_DECRYPTION_MODULE_EXPORT_H_