Issue #2073 - m-c 523950: Discard decoded frames of very large GIF animations (squashed)

Controlled by image.animated.decode-on-demand.threshold-kb, default 256MB

Includes squashed bugfixes/regressions:
 - m-c 1444537: Shutting down the decode pool should make animated decoders bail early
 - m-c 1628606: Make sure to mark the surface cache entry available before sending the frame complete notification
 - m-c 1502275: Skip recreating the decoder after redecode errors if an animated image is reset
 - m-c 1443232: Don't insert frames into our AnimationFrameBuffer that we consider in error and unusable

1 files changed, 28 insertions, 8 deletions

diff --git a/image/FrameAnimator.cpp b/image/FrameAnimator.cpp
index 066da94f40..b9a4aec4a8 100644
--- a/image/FrameAnimator.cpp
+++ b/image/FrameAnimator.cpp
@@ -64,12 +64,7 @@ AnimationState::UpdateStateInternal(LookupResult& aResult,
     if (mHasBeenDecoded) {
       Maybe<uint32_t> frameCount = FrameCount();
       MOZ_ASSERT(frameCount.isSome());
-      aResult.Surface().Seek(*frameCount - 1);
-      if (aResult.Surface() && aResult.Surface()->IsFinished()) {
-        mIsCurrentlyDecoded = true;
-      } else {
-        mIsCurrentlyDecoded = false;
-      }
+      mIsCurrentlyDecoded = aResult.Surface().IsFullyDecoded();
     }
   }
 
@@ -286,8 +281,12 @@ FrameAnimator::AdvanceFrame(AnimationState& aState,
   // failure) we would have discarded all the old frames and may not yet have
   // the new ones.
   if (!nextFrame || !nextFrame->IsFinished()) {
-    // Uh oh, the frame we want to show is currently being decoded (partial)
-    // Wait until the next refresh driver tick and try again
+    // Uh oh, the frame we want to show is currently being decoded (partial).
+    // Similar to the above case, we could be blocked by network or decoding,
+    // and so we should advance our current time rather than risk jumping
+    // through the animation. We will wait until the next refresh driver tick
+    // and try again.
+    aState.mCurrentAnimationFrameTime = aTime;
     return ret;
   }
 
@@ -313,6 +312,7 @@ FrameAnimator::AdvanceFrame(AnimationState& aState,
       MOZ_ASSERT(currentFrameEndTime.isSome());
       aState.mCurrentAnimationFrameTime = *currentFrameEndTime;
       aState.mCurrentAnimationFrameIndex = nextFrameIndex;
+      aFrames.Advance(nextFrameIndex);
 
       return ret;
     }
@@ -343,6 +343,7 @@ FrameAnimator::AdvanceFrame(AnimationState& aState,
 
   // Set currentAnimationFrameIndex at the last possible moment
   aState.mCurrentAnimationFrameIndex = nextFrameIndex;
+  aFrames.Advance(nextFrameIndex);
 
   // If we're here, we successfully advanced the frame.
   ret.mFrameAdvanced = true;
@@ -350,6 +351,25 @@ FrameAnimator::AdvanceFrame(AnimationState& aState,
   return ret;
 }
 
+void
+FrameAnimator::ResetAnimation(AnimationState& aState)
+{
+  aState.ResetAnimation();
+
+  // Our surface provider is synchronized to our state, so we need to reset its
+  // state as well, if we still have one.
+  LookupResult result =
+    SurfaceCache::Lookup(ImageKey(mImage),
+                         RasterSurfaceKey(mSize,
+                                          DefaultSurfaceFlags(),
+                                          PlaybackType::eAnimated));
+  if (!result) {
+    return;
+  }
+
+  result.Surface().Reset();
+}
+
 RefreshResult
 FrameAnimator::RequestRefresh(AnimationState& aState,
                               const TimeStamp& aTime,