GrResourceCache2 manages scratch texture.

src/gpu/GrClipMaskCache.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrClipMaskCache_DEFINED
 #define GrClipMaskCache_DEFINED
 
@@ skipping 186 matching lines @@
             this->reset();
         }
 
         void acquireMask(GrContext* context,
                          int32_t clipGenID,
                          const GrTextureDesc& desc,
                          const SkIRect& bound) {
 
             fLastClipGenID = clipGenID;
 
-            fLastMask.set(context, desc);
+            // HACK: set the last param to true to indicate that this request is at
+            // flush time and therefore we require a scratch texture with no pending IO operations.
+            fLastMask.set(context, desc, GrContext::kApprox_ScratchTexMatch, /*flushing=*/true);
 
             fLastBound = bound;
         }
 
         void reset () {
             fLastClipGenID = SkClipStack::kInvalidGenID;
 
             GrTextureDesc desc;
 
             fLastMask.set(NULL, desc);
@@ skipping 10 matching lines @@
         SkIRect                 fLastBound;
     };
 
     GrContext*   fContext;
     SkDeque      fStack;
 
     typedef SkNoncopyable INHERITED;
 };
 
 #endif // GrClipMaskCache_DEFINED