Move LayoutObject::CanRenderBorderImage to ComputedStyle

Move the CanRenderBorderImage method from LayoutObject to ComputedStyle.
It only depends on information from ComputedStyle and it is not virtual.

Change-Id: I175d4b21b8d1e4f2f8e5535fc063dc65be0b841f
Reviewed-on: https://chromium-review.googlesource.com/565655Reviewed-by: Walter Korman <wkorman@chromium.org>
Commit-Queue: Emil A Eklund <eae@chromium.org>
Cr-Commit-Position: refs/heads/master@{#485455}

third_party/WebKit/Source/core/layout/LayoutBox.cpp

@@ -5729,7 +5729,7 @@ bool LayoutBox::MustInvalidateBackgroundOrBorderPaintOnWidthChange() const {
     return true;
 
   // Our fill layers are ok. Let's check border.
-  if (Style()->HasBorderDecoration() && CanRenderBorderImage())
+  if (Style()->CanRenderBorderImage())
     return true;
 
   return false;
@@ -5748,20 +5748,12 @@ bool LayoutBox::MustInvalidateBackgroundOrBorderPaintOnHeightChange() const {
     return true;
 
   // Our fill layers are ok.  Let's check border.
-  if (Style()->HasBorderDecoration() && CanRenderBorderImage())
+  if (Style()->CanRenderBorderImage())
     return true;
 
   return false;
 }
 
-bool LayoutBox::CanRenderBorderImage() const {
-  if (!Style()->HasBorderDecoration())
-    return false;
-
-  StyleImage* border_image = Style()->BorderImage().GetImage();
-  return border_image && border_image->CanRender() && border_image->IsLoaded();
-}
-
 ShapeOutsideInfo* LayoutBox::GetShapeOutsideInfo() const {
   return ShapeOutsideInfo::IsEnabledFor(*this) ? ShapeOutsideInfo::Info(*this)
                                                : nullptr;

third_party/WebKit/Source/core/paint/BoxDecorationData.cpp

@@ -21,7 +21,13 @@ BoxDecorationData::BoxDecorationData(const LayoutBox& layout_box) {
   DCHECK(has_background == layout_box.Style()->HasBackground());
   has_border_decoration = layout_box.Style()->HasBorderDecoration();
   has_appearance = layout_box.Style()->HasAppearance();
-  bleed_avoidance = DetermineBackgroundBleedAvoidance(layout_box);
+  if (layout_box.IsDocumentElement()) {
+    bleed_avoidance = kBackgroundBleedNone;
+  } else {
+    bleed_avoidance = DetermineBackgroundBleedAvoidance(
+        layout_box.GetDocument(), layout_box.StyleRef(),
+        layout_box.BackgroundShouldAlwaysBeClipped());
+  }
 }
 
 namespace {
@@ -41,37 +47,34 @@ bool BorderObscuresBackgroundEdge(const ComputedStyle& style) {
 }  // anonymous namespace
 
 BackgroundBleedAvoidance BoxDecorationData::DetermineBackgroundBleedAvoidance(
-    const LayoutBox& layout_box) {
-  if (layout_box.IsDocumentElement())
-    return kBackgroundBleedNone;
-
+    const Document& document,
+    const ComputedStyle& style,
+    bool background_should_always_be_clipped) {
   if (!has_background)
     return kBackgroundBleedNone;
 
-  const ComputedStyle& box_style = layout_box.StyleRef();
-  const bool has_border_radius = box_style.HasBorderRadius();
+  const bool has_border_radius = style.HasBorderRadius();
   if (!has_border_decoration || !has_border_radius ||
-      layout_box.CanRenderBorderImage()) {
-    if (layout_box.BackgroundShouldAlwaysBeClipped())
+      style.CanRenderBorderImage()) {
+    if (background_should_always_be_clipped)
       return kBackgroundBleedClipOnly;
     // Border radius clipping may require layer bleed avoidance if we are going
     // to draw an image over something else, because we do not want the
     // antialiasing to lead to bleeding
-    if (box_style.HasBackgroundImage() && has_border_radius) {
+    if (style.HasBackgroundImage() && has_border_radius) {
       // But if the top layer is opaque for the purposes of background painting,
       // we do not need the bleed avoidance because we will not paint anything
       // behind the top layer.  But only if we need to draw something
       // underneath.
-      const FillLayer& fill_layer = layout_box.Style()->BackgroundLayers();
+      const FillLayer& fill_layer = style.BackgroundLayers();
       if ((background_color.Alpha() || fill_layer.Next()) &&
-          !fill_layer.ImageOccludesNextLayers(layout_box.GetDocument(),
-                                              box_style))
+          !fill_layer.ImageOccludesNextLayers(document, style))
         return kBackgroundBleedClipLayer;
     }
     return kBackgroundBleedNone;
   }
 
-  if (BorderObscuresBackgroundEdge(box_style))
+  if (BorderObscuresBackgroundEdge(style))
     return kBackgroundBleedShrinkBackground;
 
   return kBackgroundBleedClipLayer;

third_party/WebKit/Source/core/paint/BoxDecorationData.h

@@ -11,6 +11,8 @@
 namespace blink {
 
 class LayoutBox;
+class Document;
+class ComputedStyle;
 
 // Information extracted from ComputedStyle for box painting.
 struct BoxDecorationData {
@@ -26,7 +28,10 @@ struct BoxDecorationData {
   bool has_appearance;
 
  private:
-  BackgroundBleedAvoidance DetermineBackgroundBleedAvoidance(const LayoutBox&);
+  BackgroundBleedAvoidance DetermineBackgroundBleedAvoidance(
+      const Document&,
+      const ComputedStyle&,
+      bool background_should_always_be_clipped);
 };
 
 }  // namespace blink

third_party/WebKit/Source/core/style/ComputedStyle.cpp

@@ -1096,6 +1096,14 @@ FloatRoundedRect ComputedStyle::GetRoundedInnerBorderFor(
   return rounded_rect;
 }
 
+bool ComputedStyle::CanRenderBorderImage() const {
+  if (!HasBorderDecoration())
+    return false;
+
+  StyleImage* border_image = BorderImage().GetImage();
+  return border_image && border_image->CanRender() && border_image->IsLoaded();
+}
+
 static bool AllLayersAreFixed(const FillLayer& layer) {
   for (const FillLayer* curr_layer = &layer; curr_layer;
        curr_layer = curr_layer->Next()) {

third_party/WebKit/Source/core/style/ComputedStyle.h

@@ -1812,6 +1812,8 @@ class ComputedStyle : public ComputedStyleBase,
       bool include_logical_left_edge,
       bool include_logical_right_edge) const;
 
+  bool CanRenderBorderImage() const;
+
   // Float utility functions.
   bool IsFloating() const { return Floating() != EFloat::kNone; }