Optimize CSS box-shadow performance

src/core/SkBitmapCache.h

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkBitmapCache_DEFINED
 #define SkBitmapCache_DEFINED
 
+#include "SkRect.h"
+#include "SkRRect.h"
 #include "SkScaledImageCache.h"
 
 class SkBitmapCache {
 public:
     typedef SkScaledImageCache::ID ID;
 
     static void Unlock(ID* id) {
         SkScaledImageCache::Unlock(id);
     }
 
     /* Input: bitmap+inverse_scale */
     static ID* FindAndLock(const SkBitmap& src, SkScalar invScaleX, SkScalar invScaleY,
                            SkBitmap* result);
     static ID* AddAndLock(const SkBitmap& src, SkScalar invScaleX, SkScalar invScaleY,
                           const SkBitmap& result);
 
     /* Input: bitmap_genID+width+height */
     static ID* FindAndLock(uint32_t genID, int width, int height, SkBitmap* result);
 
     static ID* AddAndLock(uint32_t genID, int width, int height, const SkBitmap& result);
+
+    /* Input: blur_sigma+rrect */
+    static ID* FindAndLock(SkScalar sigma, const SkRRect rrect, SkBitmap* result);
+    static ID* AddAndLock(SkScalar sigma, const SkRRect rrect, const SkBitmap& bitmap);
+
+    /* Input: blur_sigma+rects_count+rects */
+    static ID* FindAndLock(SkScalar sigma, unsigned count, const SkRect rects[],
+                           SkBitmap* result);
+    static ID* AddAndLock(SkScalar sigma, unsigned count, const SkRect rects[],
+                          const SkBitmap& bitmap);
 };
 
 class SkMipMapCache {
 public:
     typedef SkScaledImageCache::ID ID;
 
     static void Unlock(ID* id) {
         SkScaledImageCache::Unlock(id);
     }
 
     static ID* FindAndLock(const SkBitmap& src, const SkMipMap** result);
     static ID* AddAndLock(const SkBitmap& src, const SkMipMap* result);
 };
 
 #endif