Bug 1660122 Part 5 - Add nsIFrame::GetAspectRatio() skeleton, and adapt existing callers. r=emilio

For now, GetAspectRatio() is just an alias for GetIntrinicRatio(). In
Part 7, we're going to have GetAspectRatio() consider aspect-ratio
property so that each replaced elements only need to report their
intrinsic ratio via GetIntrinicRatio(). Non-replaced element can also
call GetAspectRatio() to get the ratio suitable to calculate layout
size.

As of this patch, all the replaced elements'
GetIntrinsicRatio() (including nsImageFrame::mIntrinsicRatio) consider
aspect-ratio properties (added in bug 1639963). This is wrong, because
it affects replaced element's content ratio. So we adapt only callers
[1] involving the computation of the frame's external sizes to retain
the behavior after Part 7.

This change shouldn't change behavior.

[1] Exceptions include 1) a caller in nsIFrame::ComputeSize() checking
the frame has no intrinsic ratio; 2) other frame classes implementing
nsIFrame::GetIntrinsicRatio() by calling their parent's
GetIntrinicRatio(). nsSubDocumentFrame::GetIntrinicRatio() is an
example.

Differential Revision: https://phabricator.services.mozilla.com/D91227

layout/base/nsLayoutUtils.cpp

@@ -5776,7 +5776,7 @@ nscoord nsLayoutUtils::IntrinsicForAxis(
         !(styleMinBSize.IsAuto() || (styleMinBSize.ConvertsToLength() &&
                                      styleMinBSize.ToLength() == 0)) ||
         !styleMaxBSize.IsNone()) {
-      if (AspectRatio ratio = aFrame->GetIntrinsicRatio()) {
+      if (AspectRatio ratio = aFrame->GetAspectRatio()) {
         // Convert 'ratio' if necessary, so that it's storing ISize/BSize:
         if (!horizontalAxis) {
           ratio = ratio.Inverted();

layout/generic/nsFlexContainerFrame.cpp

@@ -2053,7 +2053,7 @@ FlexItem::FlexItem(ReflowInput& aFlexItemReflowInput, float aFlexGrow,
     : mFrame(aFlexItemReflowInput.mFrame),
       mFlexGrow(aFlexGrow),
       mFlexShrink(aFlexShrink),
-      mIntrinsicRatio(mFrame->GetIntrinsicRatio()),
+      mIntrinsicRatio(mFrame->GetAspectRatio()),
       mWM(aFlexItemReflowInput.GetWritingMode()),
       mCBWM(aAxisTracker.GetWritingMode()),
       mMainAxis(aAxisTracker.MainAxis()),

layout/generic/nsIFrame.cpp

@@ -5962,6 +5962,11 @@ IntrinsicSize nsIFrame::GetIntrinsicSize() {
   return IntrinsicSize();  // default is width/height set to eStyleUnit_None
 }
 
+AspectRatio nsIFrame::GetAspectRatio() const {
+  // TODO: Consider aspect-ratio property.
+  return GetIntrinsicRatio();
+}
+
 /* virtual */
 AspectRatio nsIFrame::GetIntrinsicRatio() const { return AspectRatio(); }
 

layout/generic/nsIFrame.h

@@ -2663,12 +2663,21 @@ class nsIFrame : public nsQueryFrame {
   virtual mozilla::IntrinsicSize GetIntrinsicSize();
 
   /**
-   * Get the intrinsic ratio of this element, or a default-constructed
+   * Get the preferred aspect ratio of this frame, or a default-constructed
+   * AspectRatio if it has none.
+   *
+   * https://drafts.csswg.org/css-sizing-4/#preferred-aspect-ratio
+   */
+  mozilla::AspectRatio GetAspectRatio() const;
+
+  /**
+   * Get the intrinsic aspect ratio of this frame, or a default-constructed
    * AspectRatio if it has no intrinsic ratio.
    *
    * The intrinsic ratio is the ratio of the width/height of a box with an
    * intrinsic size or the intrinsic aspect ratio of a scalable vector image
-   * without an intrinsic size.
+   * without an intrinsic size. A frame class implementing a replaced element
+   * should override this method if it has a intrinsic ratio.
    */
   virtual mozilla::AspectRatio GetIntrinsicRatio() const;
 

layout/generic/nsImageFrame.cpp

@@ -947,7 +947,7 @@ nsIFrame::SizeComputationResult nsImageFrame::ComputeSize(
     const LogicalSize& aBorderPadding, ComputeSizeFlags aFlags) {
   EnsureIntrinsicSizeAndRatio();
   return {ComputeSizeWithIntrinsicDimensions(
-              aRenderingContext, aWM, mIntrinsicSize, mIntrinsicRatio, aCBSize,
+              aRenderingContext, aWM, mIntrinsicSize, GetAspectRatio(), aCBSize,
               aMargin, aBorderPadding, aFlags),
           AspectRatioUsage::None};
 }

layout/generic/nsLineLayout.cpp

@@ -728,7 +728,7 @@ static bool IsPercentageAware(const nsIFrame* aFrame, WritingMode aWM) {
     //   is calculated from the constraint equation used for
     //   block-level, non-replaced elements in normal flow.
     nsIFrame* f = const_cast<nsIFrame*>(aFrame);
-    if (f->GetIntrinsicRatio() &&
+    if (f->GetAspectRatio() &&
         // Some percents are treated like 'auto', so check != coord
         !pos->BSize(aWM).ConvertsToLength()) {
       const IntrinsicSize& intrinsicSize = f->GetIntrinsicSize();

layout/generic/nsSubDocumentFrame.cpp

@@ -688,7 +688,7 @@ nsIFrame::SizeComputationResult nsSubDocumentFrame::ComputeSize(
     nscoord aAvailableISize, const LogicalSize& aMargin,
     const LogicalSize& aBorderPadding, ComputeSizeFlags aFlags) {
   return {ComputeSizeWithIntrinsicDimensions(
-              aRenderingContext, aWM, GetIntrinsicSize(), GetIntrinsicRatio(),
+              aRenderingContext, aWM, GetIntrinsicSize(), GetAspectRatio(),
               aCBSize, aMargin, aBorderPadding, aFlags),
           AspectRatioUsage::None};
 }

layout/generic/nsVideoFrame.cpp

@@ -576,9 +576,8 @@ nsIFrame::SizeComputationResult nsVideoFrame::ComputeSize(
   nsSize size = GetVideoIntrinsicSize(aRenderingContext);
   IntrinsicSize intrinsicSize(size.width, size.height);
 
-  auto intrinsicRatio = GetIntrinsicRatio();
   return {ComputeSizeWithIntrinsicDimensions(
-              aRenderingContext, aWM, intrinsicSize, intrinsicRatio, aCBSize,
+              aRenderingContext, aWM, intrinsicSize, GetAspectRatio(), aCBSize,
               aMargin, aBorderPadding, aFlags),
           AspectRatioUsage::None};
 }

layout/svg/SVGOuterSVGFrame.cpp

@@ -362,8 +362,8 @@ nsIFrame::SizeComputationResult SVGOuterSVGFrame::ComputeSize(
   }
 
   return {ComputeSizeWithIntrinsicDimensions(
-              aRenderingContext, aWritingMode, intrinsicSize,
-              GetIntrinsicRatio(), cbSize, aMargin, aBorderPadding, aFlags),
+              aRenderingContext, aWritingMode, intrinsicSize, GetAspectRatio(),
+              cbSize, aMargin, aBorderPadding, aFlags),
           AspectRatioUsage::None};
 }
 
@@ -914,7 +914,7 @@ void SVGOuterSVGFrame::AppendDirectlyOwnedAnonBoxes(
 
 void SVGOuterSVGFrame::MaybeSendIntrinsicSizeAndRatioToEmbedder() {
   MaybeSendIntrinsicSizeAndRatioToEmbedder(Some(GetIntrinsicSize()),
-                                           Some(GetIntrinsicRatio()));
+                                           Some(GetAspectRatio()));
 }
 
 void SVGOuterSVGFrame::MaybeSendIntrinsicSizeAndRatioToEmbedder(