Revert of GrResourceCache2 manages scratch texture.

include/gpu/GrContext.h

 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrContext_DEFINED
 #define GrContext_DEFINED
 
@@ skipping 277 matching lines @@
      *
      * Textures created by createAndLockTexture() hide the complications of
      * tiling non-power-of-two textures on APIs that don't support this (e.g.
      * unextended GLES2). Tiling a NPOT texture created by lockScratchTexture on
      * such an API will create gaps in the tiling pattern. This includes clamp
      * mode. (This may be addressed in a future update.)
      */
     GrTexture* lockAndRefScratchTexture(const GrTextureDesc&, ScratchTexMatch match);
 
     /**
+     *  When done with an entry, call unlockScratchTexture(entry) on it, which returns
+     *  it to the cache, where it may be purged. This does not unref the texture.
+     */
+    void unlockScratchTexture(GrTexture* texture);
+
+    /**
      * Creates a texture that is outside the cache. Does not count against
      * cache's budget.
      */
     GrTexture* createUncachedTexture(const GrTextureDesc& desc,
                                      void* srcData,
                                      size_t rowBytes);
 
     /**
      * Returns true if the specified use of an indexed texture is supported.
      * Support may depend upon whether the texture params indicate that the
@@ skipping 730 matching lines @@
 
     void internalDrawPath(GrDrawTarget* target, bool useAA, const SkPath& path,
                           const GrStrokeInfo& stroke);
 
     GrTexture* createResizedTexture(const GrTextureDesc& desc,
                                     const GrCacheID& cacheID,
                                     const void* srcData,
                                     size_t rowBytes,
                                     bool filter);
 
-    bool createNewScratchTexture(const GrTextureDesc& desc);
+    // Needed so GrTexture's returnToCache helper function can call
+    // addExistingTextureToCache
+    friend class GrTexture;
+    friend class GrStencilAndCoverPathRenderer;
+    friend class GrStencilAndCoverTextContext;
+
+    // Add an existing texture to the texture cache. This is intended solely
+    // for use with textures released from an GrAutoScratchTexture.
+    void addExistingTextureToCache(GrTexture* texture);
 
     /**
      * These functions create premul <-> unpremul effects if it is possible to generate a pair
      * of effects that make a readToUPM->writeToPM->readToUPM cycle invariant. Otherwise, they
      * return NULL.
      */
     const GrFragmentProcessor* createPMToUPMEffect(GrTexture*, bool swapRAndB, const SkMatrix&);
     const GrFragmentProcessor* createUPMToPMEffect(GrTexture*, bool swapRAndB, const SkMatrix&);
 
     /**
      *  This callback allows the resource cache to callback into the GrContext
      *  when the cache is still overbudget after a purge.
      */
     static bool OverbudgetCB(void* data);
 
     typedef SkRefCnt INHERITED;
 };
 
 /**
- * This is deprecated. Don't use it.
+ * Gets and locks a scratch texture from a descriptor using either exact or approximate criteria.
+ * Unlocks texture in the destructor.
  */
 class GrAutoScratchTexture : public ::SkNoncopyable {
 public:
     GrAutoScratchTexture()
         : fContext(NULL)
         , fTexture(NULL) {
     }
 
     GrAutoScratchTexture(GrContext* context,
                          const GrTextureDesc& desc,
                          GrContext::ScratchTexMatch match = GrContext::kApprox_ScratchTexMatch)
       : fContext(NULL)
       , fTexture(NULL) {
       this->set(context, desc, match);
     }
 
     ~GrAutoScratchTexture() {
         this->reset();
     }
 
     void reset() {
         if (fContext && fTexture) {
+            fContext->unlockScratchTexture(fTexture);
             fTexture->unref();
             fTexture = NULL;
         }
     }
 
-    GrTexture* detach() {
-        GrTexture* texture = fTexture;
-        fTexture = NULL;
-        return texture;
-    }
+    /*
+     * When detaching a texture we do not unlock it in the texture cache but
+     * we do set the returnToCache flag. In this way the texture remains
+     * "locked" in the texture cache until it is freed and recycled in
+     * GrTexture::internal_dispose. In reality, the texture has been removed
+     * from the cache (because this is in AutoScratchTexture) and by not
+     * calling unlockScratchTexture we simply don't re-add it. It will be
+     * reattached in GrTexture::internal_dispose.
+     *
+     * Note that the caller is assumed to accept and manage the ref to the
+     * returned texture.
+     */
+    GrTexture* detach();
 
     GrTexture* set(GrContext* context,
                    const GrTextureDesc& desc,
                    GrContext::ScratchTexMatch match = GrContext::kApprox_ScratchTexMatch) {
         this->reset();
 
         fContext = context;
         if (fContext) {
             fTexture = fContext->lockAndRefScratchTexture(desc, match);
             if (NULL == fTexture) {
                 fContext = NULL;
             }
             return fTexture;
         } else {
             return NULL;
         }
     }
 
     GrTexture* texture() { return fTexture; }
 
 private:
     GrContext*                    fContext;
     GrTexture*                    fTexture;
 };
 
 #endif