Support subpixel layout for borders.

third_party/WebKit/Source/core/css/resolver/AnimatedStyleBuilder.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 111 matching lines @@
 }
 
 template <typename T>
 T animatableLineWidthClamp(const AnimatableValue* value,
                            const StyleResolverState& state) {
   double lineWidth = animatableValueToPixels(value, state);
   // This matches StyleBuilderConverter::convertLineWidth().
   return (lineWidth > 0 && lineWidth < 1) ? 1 : roundedClampTo<T>(lineWidth);
 }
 
+float animatableLineWidth(const AnimatableValue* value,
+                          const StyleResolverState& state) {
+  double lineWidth =
+      toAnimatableLength(value)
+          ->getLength(state.style()->effectiveZoom(), ValueRangeNonNegative)
+          .pixels();
+  // This matches StyleBuilderConverter::convertLineWidth().
+  return (lineWidth > 0 && lineWidth < 1) ? 1 : lineWidth;
+}
+
 LengthBox animatableValueToLengthBox(const AnimatableValue* value,
                                      const StyleResolverState& state,
                                      ValueRange range = ValueRangeAll) {
   const AnimatableLengthBox* animatableLengthBox = toAnimatableLengthBox(value);
   return LengthBox(
       animatableValueToLength(animatableLengthBox->top(), state, range),
       animatableValueToLength(animatableLengthBox->right(), state, range),
       animatableValueToLength(animatableLengthBox->bottom(), state, range),
       animatableValueToLength(animatableLengthBox->left(), state, range));
 }
@@ skipping 211 matching lines @@
       return;
     case CSSPropertyBorderBottomLeftRadius:
       style->setBorderBottomLeftRadius(
           animatableValueToLengthSize(value, state, ValueRangeNonNegative));
       return;
     case CSSPropertyBorderBottomRightRadius:
       style->setBorderBottomRightRadius(
           animatableValueToLengthSize(value, state, ValueRangeNonNegative));
       return;
     case CSSPropertyBorderBottomWidth:
-      style->setBorderBottomWidth(
-          animatableLineWidthClamp<unsigned>(value, state));
+      style->setBorderBottomWidth(animatableLineWidth(value, state));
       return;
     case CSSPropertyBorderImageOutset:
       style->setBorderImageOutset(
           animatableValueToBorderImageLengthBox(value, state));
       return;
     case CSSPropertyBorderImageSlice:
       style->setBorderImageSlices(
           animatableValueToLengthBox(toAnimatableLengthBoxAndBool(value)->box(),
                                      state, ValueRangeNonNegative));
       style->setBorderImageSlicesFill(
           toAnimatableLengthBoxAndBool(value)->flag());
       return;
     case CSSPropertyBorderImageSource:
       style->setBorderImageSource(
           state.styleImage(property, *toAnimatableImage(value)->toCSSValue()));
       return;
     case CSSPropertyBorderImageWidth:
       style->setBorderImageWidth(
           animatableValueToBorderImageLengthBox(value, state));
       return;
     case CSSPropertyBorderLeftColor:
       style->setBorderLeftColor(toAnimatableColor(value)->getColor());
       style->setVisitedLinkBorderLeftColor(
           toAnimatableColor(value)->visitedLinkColor());
       return;
     case CSSPropertyBorderLeftWidth:
-      style->setBorderLeftWidth(
-          animatableLineWidthClamp<unsigned>(value, state));
+      style->setBorderLeftWidth(animatableLineWidth(value, state));
       return;
     case CSSPropertyBorderRightColor:
       style->setBorderRightColor(toAnimatableColor(value)->getColor());
       style->setVisitedLinkBorderRightColor(
           toAnimatableColor(value)->visitedLinkColor());
       return;
     case CSSPropertyBorderRightWidth:
-      style->setBorderRightWidth(
-          animatableLineWidthClamp<unsigned>(value, state));
+      style->setBorderRightWidth(animatableLineWidth(value, state));
       return;
     case CSSPropertyBorderTopColor:
       style->setBorderTopColor(toAnimatableColor(value)->getColor());
       style->setVisitedLinkBorderTopColor(
           toAnimatableColor(value)->visitedLinkColor());
       return;
     case CSSPropertyBorderTopLeftRadius:
       style->setBorderTopLeftRadius(
           animatableValueToLengthSize(value, state, ValueRangeNonNegative));
       return;
     case CSSPropertyBorderTopRightRadius:
       style->setBorderTopRightRadius(
           animatableValueToLengthSize(value, state, ValueRangeNonNegative));
       return;
     case CSSPropertyBorderTopWidth:
-      style->setBorderTopWidth(
-          animatableLineWidthClamp<unsigned>(value, state));
+      style->setBorderTopWidth(animatableLineWidth(value, state));
       return;
     case CSSPropertyBottom:
       style->setBottom(animatableValueToLength(value, state));
       return;
     case CSSPropertyBoxShadow:
       style->setBoxShadow(toAnimatableShadow(value)->getShadowList());
       return;
     case CSSPropertyCaretColor:
       style->setCaretColor(toAnimatableColor(value)->getColor());
       style->setVisitedLinkCaretColor(
@@ skipping 422 matching lines @@
       style->setRy(
           animatableValueToLength(value, state, ValueRangeNonNegative));
       return;
 
     default:
       ASSERT_NOT_REACHED();
   }
 }
 
 }  // namespace blink