Refactor LocalBorderBoxProperties to use PropertyTreeState

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

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/paint/ObjectPaintProperties.h"
 
 namespace blink {
 
-void ObjectPaintProperties::getContentsProperties(GeometryPropertyTreeState& properties) const

[chrishtr, 2016/09/26 17:09:51]

The old code was optimized to remove an extra copy constructor of
GeometryPropertyTreeState.

+GeometryPropertyTreeState ObjectPaintProperties::getContentsProperties() const
 {
-    properties = localBorderBoxProperties()->geometryPropertyTreeState;
+    const LocalBorderBoxProperties* localBorderBox = localBorderBoxProperties();
+    GeometryPropertyTreeState geometryPropertyTreeState(
+        localBorderBox->propertyTreeState.transform,
+        localBorderBox->propertyTreeState.clip,
+        localBorderBox->propertyTreeState.effect);
     if (scrollTranslation())
-        properties.transform = scrollTranslation();
+        geometryPropertyTreeState.transform = scrollTranslation();
     else if (svgLocalToBorderBoxTransform())
-        properties.transform = svgLocalToBorderBoxTransform();
+        geometryPropertyTreeState.transform = svgLocalToBorderBoxTransform();
 
     if (overflowClip())
-        properties.clip = overflowClip();
+        geometryPropertyTreeState.clip = overflowClip();
     else if (cssClip())

[szager1, 2016/09/24 01:30:17]

Is it possible to have both overflow and css clip?

[chrishtr, 2016/09/26 17:09:51]

yes

-        properties.clip = cssClip();
+        geometryPropertyTreeState.clip = cssClip();
+
     // TODO(chrishtr): cssClipFixedPosition needs to be handled somehow.
+
+    return geometryPropertyTreeState;
 }
 
 } // namespace blink