Share GeometryMapper cache between pre-paint and compositing.

third_party/WebKit/Source/platform/graphics/paint/GeometryMapper.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 "platform/graphics/paint/GeometryMapper.h"
 
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/geometry/LayoutRect.h"
 
 namespace blink {
@@ skipping 265 matching lines @@
        it++) {
     TransformationMatrix localTransformMatrix = (*it)->matrix();
     localTransformMatrix.applyTransformOrigin((*it)->origin());
     transformMatrix = transformMatrix * localTransformMatrix;
     precomputedData.toAncestorTransforms.set(*it, transformMatrix);
   }
   success = true;
   return precomputedData.toAncestorTransforms.find(localTransformNode)->value;
 }
 
+void GeometryMapper::clearCache() {
+  m_data.clear();
+}
+
 namespace {
 
 template <typename NodeType>
 unsigned nodeDepth(const NodeType* node) {
   unsigned depth = 0;
   while (node) {
     depth++;
     node = node->parent();
   }
   return depth;
@@ skipping 38 matching lines @@
     const TransformPaintPropertyNode*,
     const TransformPaintPropertyNode*);
 template const ClipPaintPropertyNode* GeometryMapper::lowestCommonAncestor(
     const ClipPaintPropertyNode*,
     const ClipPaintPropertyNode*);
 template const ScrollPaintPropertyNode* GeometryMapper::lowestCommonAncestor(
     const ScrollPaintPropertyNode*,
     const ScrollPaintPropertyNode*);
 
 }  // namespace blink