Handle border-image with fill and zero-width borders

Source/core/style/ComputedStyle.h

Index: Source/core/style/ComputedStyle.h
diff --git a/Source/core/style/ComputedStyle.h b/Source/core/style/ComputedStyle.h
index 64abb5eb0ef055f4949c15f8119748e51432bb07..90b28a5c8b9a4ab9c96a98bbb7cc85b6bea201b8 100644
--- a/Source/core/style/ComputedStyle.h
+++ b/Source/core/style/ComputedStyle.h
@@ -390,7 +390,9 @@ public:
     bool operator!=(const ComputedStyle& other) const { return !(*this == other); }
     bool isFloating() const { return noninherited_flags.floating != NoFloat; }
     bool hasMargin() const { return surround->margin.nonZero(); }
+    bool hasBorderFill() const { return surround->border.hasBorderFill(); }
     bool hasBorder() const { return surround->border.hasBorder(); }
+    bool hasBorderDecoration() const { return hasBorder() || hasBorderFill(); }

[pdr., 2015/06/02 03:07:56]

Can the hasBorder and image check in ComputedStyle::borderObscuresBackground be
replaced with hasBorderDecoration?

[davve, 2015/06/03 06:56:01]

You mean replacing

    if (!hasBorder())
        return false;

    // Bail if we have any border-image for now. We could look at the image
alpha to improve this.
    if (borderImage().image())
        return false;

    ...

with:

    if (!hasBorderDecoration())
        return false;

    ...

Such a change would mean that we would go on to inspect edges for the
case when all border widths are zero but there still is a border-image
to draw. Since we don't inspect the alpha channel of the border-image,
I think border-image should mean we always bail.

     bool hasPadding() const { return surround->padding.nonZero(); }
     bool hasMarginBeforeQuirk() const { return marginBefore().quirk(); }
     bool hasMarginAfterQuirk() const { return marginAfter().quirk(); }
@@ -1512,7 +1514,7 @@ public:
     bool hasChildDependentFlags() const { return emptyState() || hasExplicitlyInheritedProperties(); }
     void copyChildDependentFlagsFrom(const ComputedStyle&);
 
-    bool hasBoxDecorations() const { return hasBorder() || hasBorderRadius() || hasOutline() || hasAppearance() || boxShadow() || hasFilter() || resize() != RESIZE_NONE; }
+    bool hasBoxDecorations() const { return hasBorderDecoration() || hasBorderRadius() || hasOutline() || hasAppearance() || boxShadow() || hasFilter() || resize() != RESIZE_NONE; }
 
     bool borderObscuresBackground() const;
     void getBorderEdgeInfo(BorderEdge edges[], bool includeLogicalLeftEdge = true, bool includeLogicalRightEdge = true) const;