Improve performance of GeometryMapper cache.

third_party/WebKit/Source/platform/graphics/paint/TransformPaintPropertyNode.h

 // Copyright 2015 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.
 
 #ifndef TransformPaintPropertyNode_h
 #define TransformPaintPropertyNode_h
 
 #include "platform/PlatformExport.h"
 #include "platform/geometry/FloatPoint3D.h"
 #include "platform/graphics/CompositingReasons.h"
 #include "platform/graphics/CompositorElementId.h"
+#include "platform/graphics/paint/GeometryMapperTransformCache.h"
 #include "platform/graphics/paint/ScrollPaintPropertyNode.h"
 #include "platform/transforms/TransformationMatrix.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/RefPtr.h"
 #include "wtf/text/WTFString.h"
 
 #include <iosfwd>
 
 namespace blink {
@@ skipping 178 matching lines @@
       PassRefPtr<ScrollPaintPropertyNode> scroll = nullptr)
       : m_parent(parent),
         m_matrix(matrix),
         m_origin(origin),
         m_flattensInheritedTransform(flattensInheritedTransform),
         m_renderingContextId(renderingContextId),
         m_directCompositingReasons(directCompositingReasons),
         m_compositorElementId(compositorElementId),
         m_scroll(scroll) {}
 
+  // For access to getTransformCache() and setCachedTransform.
+  friend class GeometryMapper;
+  friend class GeometryMapperTest;
+
+  GeometryMapperTransformCache& getTransformCache() const {
+    return const_cast<TransformPaintPropertyNode*>(this)->getTransformCache();
+  }
+
+  GeometryMapperTransformCache& getTransformCache() {
+    if (!m_geometryMapperTransformCache)
+      m_geometryMapperTransformCache.reset(new GeometryMapperTransformCache());
+    return *m_geometryMapperTransformCache.get();
+  }
+
   RefPtr<const TransformPaintPropertyNode> m_parent;
   TransformationMatrix m_matrix;
   FloatPoint3D m_origin;
   bool m_flattensInheritedTransform;
   unsigned m_renderingContextId;
   CompositingReasons m_directCompositingReasons;
   CompositorElementId m_compositorElementId;
   RefPtr<ScrollPaintPropertyNode> m_scroll;
+
+  std::unique_ptr<GeometryMapperTransformCache> m_geometryMapperTransformCache;
 };
 
 // Redeclared here to avoid ODR issues.
 // See platform/testing/PaintPrinters.h.
 void PrintTo(const TransformPaintPropertyNode&, std::ostream*);
 
 }  // namespace blink
 
 #endif  // TransformPaintPropertyNode_h