retool image cache to be generic cache

src/core/SkBitmapCache.h

Index: src/core/SkBitmapCache.h
diff --git a/src/core/SkBitmapCache.h b/src/core/SkBitmapCache.h
index ebade0ebd9b67fa277d6e9b2407cd2e691f20676..80c28550a525673e8717e86e9c6647581bcb6fc3 100644
--- a/src/core/SkBitmapCache.h
+++ b/src/core/SkBitmapCache.h
@@ -14,32 +14,24 @@ 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,
+    static ID FindAndLock(const SkBitmap& src, SkScalar invScaleX, SkScalar invScaleY,
                            SkBitmap* result);
-    static ID* AddAndLock(const SkBitmap& src, SkScalar invScaleX, SkScalar invScaleY,
+    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 FindAndLock(uint32_t genID, int width, int height, SkBitmap* result);
 
-    static ID* AddAndLock(uint32_t genID, int width, int height, const SkBitmap& result);
+    static ID AddAndLock(uint32_t genID, int width, int height, const SkBitmap& result);
 };
 
 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);
+    static ID FindAndLock(const SkBitmap& src, const SkMipMap** result);
+    static ID AddAndLock(const SkBitmap& src, const SkMipMap* result);
 };
 
 #endif