Issue #1230 - Part 1: Fix Back-computing percentages for intrinsic sizing in Layout CSS-Grid

List of relevant patches applied:

1398537 part 2 - [css-multicol] Implement percentages for 'column-gap' (Gecko part).

1434478 part 1 - [css-grid] Stop back-computing percentage grid gaps when the percentage basis is indefinite. Treat them as zero sized instead.

1434478 part 2 - Stop back-computing percentage padding/margin when the percentage basis is indefinite. Treat them as zero sized instead.

1434478 part 3 - Remove IntrinsicISizeOffsetData::hPctPadding/hPctMargin members since they are now unused.

1434478 part 4 - Factor out constants like NS_UNCONSTRAINEDSIZE so they can be used in headers without needing nsIFrame.h (idempotent patch).

1434478 part 5 - Create nsLayoutUtils::ResolveToLength for resolving CSS <length-percentage> (idempotent patch).

1434478 part 6 - Propagate a percentage basis to nsIFrame::IntrinsicISizeOffsets for resolving padding/margin.

This is needed only for CSS Grid since in other cases we're only using IntrinsicISizeOffsets in the inline-axis and the percentage basis is always indefinite for *intrinsic sizing*. When calculating the intrinsic size of grid items in the grid container's block axis however, we do have a definite size for the grid area in the inline-axis and it should be used per: https://drafts.csswg.org/css-grid/#algo-overview "2. Next, the track sizing algorithm resolves the sizes of the grid rows, using the grid column sizes calculated in the previous step." (Percentage padding/margin for grid items is always resolved against the grid area's inline-size nowadays.)

1 files changed, 9 insertions, 22 deletions

diff --git a/layout/generic/nsIFrame.h b/layout/generic/nsIFrame.h
index ec35684832..57f5c460c2 100644
--- a/layout/generic/nsIFrame.h
+++ b/layout/generic/nsIFrame.h
@@ -25,6 +25,7 @@
 
 #include "CaretAssociationHint.h"
 #include "FrameProperties.h"
+#include "LayoutConstants.h"
 #include "mozilla/layout/FrameChildList.h"
 #include "mozilla/Maybe.h"
 #include "mozilla/WritingModes.h"
@@ -130,30 +131,12 @@ typedef uint32_t nsSplittableType;
 #define NS_FRAME_IS_NOT_SPLITTABLE(type)\
   (0 == ((type) & NS_FRAME_SPLITTABLE))
 
-#define NS_INTRINSIC_WIDTH_UNKNOWN nscoord_MIN
-
 //----------------------------------------------------------------------
 
 #define NS_SUBTREE_DIRTY(_frame)  \
   (((_frame)->GetStateBits() &      \
     (NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN)) != 0)
 
-/**
- * Constant used to indicate an unconstrained size.
- *
- * @see #Reflow()
- */
-#define NS_UNCONSTRAINEDSIZE NS_MAXSIZE
-
-#define NS_INTRINSICSIZE    NS_UNCONSTRAINEDSIZE
-#define NS_AUTOHEIGHT       NS_UNCONSTRAINEDSIZE
-// +1 is to avoid clamped huge margin values being processed as auto margins
-#define NS_AUTOMARGIN       (NS_UNCONSTRAINEDSIZE + 1)
-#define NS_AUTOOFFSET       NS_UNCONSTRAINEDSIZE
-// NOTE: there are assumptions all over that these have the same value, namely NS_UNCONSTRAINEDSIZE
-//       if any are changed to be a value other than NS_UNCONSTRAINEDSIZE
-//       at least update AdjustComputedHeight/Width and test ad nauseum
-
 // 1 million CSS pixels less than our max app unit measure.
 // For reflowing with an "infinite" available inline space per [css-sizing].
 // (reflowing with an NS_UNCONSTRAINEDSIZE available inline size isn't allowed
@@ -2050,23 +2033,27 @@ public:
   /**
    * Return the horizontal components of padding, border, and margin
    * that contribute to the intrinsic width that applies to the parent.
+   * @param aPercentageBasis the percentage basis to use for padding/margin -
+   *   i.e. the Containing Block's inline-size
    */
   struct IntrinsicISizeOffsetData {
     nscoord hPadding, hBorder, hMargin;
-    float hPctPadding, hPctMargin;
 
     IntrinsicISizeOffsetData()
       : hPadding(0), hBorder(0), hMargin(0)
-      , hPctPadding(0.0f), hPctMargin(0.0f)
     {}
   };
-  virtual IntrinsicISizeOffsetData IntrinsicISizeOffsets() = 0;
+  virtual IntrinsicISizeOffsetData
+  IntrinsicISizeOffsets(nscoord aPercentageBasis = NS_UNCONSTRAINEDSIZE) = 0;
 
   /**
    * Return the bsize components of padding, border, and margin
    * that contribute to the intrinsic width that applies to the parent.
+   * @param aPercentageBasis the percentage basis to use for padding/margin -
+   *   i.e. the Containing Block's inline-size
    */
-  IntrinsicISizeOffsetData IntrinsicBSizeOffsets();
+  IntrinsicISizeOffsetData
+  IntrinsicBSizeOffsets(nscoord aPercentageBasis = NS_UNCONSTRAINEDSIZE);
 
   virtual mozilla::IntrinsicSize GetIntrinsicSize() = 0;