rename gradients private BitmapCache to GradientBitmapCache

src/effects/gradients/SkGradientShader.cpp

Index: src/effects/gradients/SkGradientShader.cpp
diff --git a/src/effects/gradients/SkGradientShader.cpp b/src/effects/gradients/SkGradientShader.cpp
index 7cc906336ad24cb3d0a5e204e6f00c61a211fe6c..502d73383af2b3e7b5744cf8ad715f2132281c4f 100644
--- a/src/effects/gradients/SkGradientShader.cpp
+++ b/src/effects/gradients/SkGradientShader.cpp
@@ -674,13 +674,13 @@ void SkGradientShaderBase::getGradientTableBitmap(SkBitmap* bitmap) const {
 
     ///////////////////////////////////
 
-    static SkBitmapCache* gCache;
+    static SkGradientBitmapCache* gCache;
     // each cache cost 1K of RAM, since each bitmap will be 1x256 at 32bpp
     static const int MAX_NUM_CACHED_GRADIENT_BITMAPS = 32;
     SkAutoMutexAcquire ama(gGradientCacheMutex);
 
     if (NULL == gCache) {
-        gCache = SkNEW_ARGS(SkBitmapCache, (MAX_NUM_CACHED_GRADIENT_BITMAPS));
+        gCache = SkNEW_ARGS(SkGradientBitmapCache, (MAX_NUM_CACHED_GRADIENT_BITMAPS));
     }
     size_t size = count * sizeof(int32_t);