Use presence of a content key as non-scratch indicator

include/gpu/GrGpuResource.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 GrGpuResource_DEFINED
 #define GrGpuResource_DEFINED
 
@@ skipping 52 matching lines @@
     void validate() const {
 #ifdef SK_DEBUG
         SkASSERT(fRefCnt >= 0);
         SkASSERT(fPendingReads >= 0);
         SkASSERT(fPendingWrites >= 0);
         SkASSERT(fRefCnt + fPendingReads + fPendingWrites > 0);
 #endif
     }
 
 protected:
-    GrIORef() : fRefCnt(1), fPendingReads(0), fPendingWrites(0), fIsScratch(kNo_IsScratch) { }
+    GrIORef() : fRefCnt(1), fPendingReads(0), fPendingWrites(0) { }
 
     bool internalHasPendingRead() const { return SkToBool(fPendingReads); }
     bool internalHasPendingWrite() const { return SkToBool(fPendingWrites); }
     bool internalHasPendingIO() const { return SkToBool(fPendingWrites | fPendingReads); }
 
 private:
     void addPendingRead() const {
         this->validate();
         ++fPendingReads;
     }
@@ skipping 27 matching lines @@
             }
         }
     }
 
     mutable int32_t fRefCnt;
     mutable int32_t fPendingReads;
     mutable int32_t fPendingWrites;
 
     // This class is used to manage conversion of refs to pending reads/writes.
     friend class GrGpuResourceRef;
-
-    // This is temporary until GrResourceCache is fully replaced by GrResourceCache2.
-    enum IsScratch {
-        kNo_IsScratch,
-        kYes_IsScratch
-    } fIsScratch;
-
-    friend class GrContext; // to set the above field.
-    friend class GrResourceCache; // to check the above field.
-    friend class GrResourceCache2; // to check the above field.
+    friend class GrResourceCache2; // to check IO ref counts.
 
     template <typename, GrIOType> friend class GrPendingIOResource;
 };
 
 /**
  * Base class for objects that can be kept in the GrResourceCache.
  */
 class SK_API GrGpuResource : public GrIORef<GrGpuResource> {
 public:
     SK_DECLARE_INST_COUNT(GrGpuResource)
@@ skipping 35 matching lines @@
      * Retrieves the amount of GPU memory used by this resource in bytes. It is
      * approximate since we aren't aware of additional padding or copies made
      * by the driver.
      *
      * @return the amount of GPU memory used in bytes
      */
     virtual size_t gpuMemorySize() const = 0;
 
     void setCacheEntry(GrResourceCacheEntry* cacheEntry) { fCacheEntry = cacheEntry; }
     GrResourceCacheEntry* getCacheEntry() const { return fCacheEntry; }
+    bool isScratch() const;
 
     /** 
      * If this resource can be used as a scratch resource this returns a valid
      * scratch key. Otherwise it returns a key for which isNullScratch is true.
      */
     const GrResourceKey& getScratchKey() const { return fScratchKey; }
 
+    /** 
+     * If this resource is currently cached by its contents then this will return
+     * the content key. Otherwise, NULL is returned.
+     */
+    const GrResourceKey* getContentKey() const;
+
     /**
      * Gets an id that is unique for this GrGpuResource object. It is static in that it does
      * not change when the content of the GrGpuResource object changes. This will never return
      * 0.
      */
     uint32_t getUniqueID() const { return fUniqueID; }
 
 protected:
     // This must be called by every GrGpuObject. It should be called once the object is fully
     // initialized (i.e. not in a base class constructor).
@@ skipping 57 matching lines @@
     GrResourceCacheEntry*   fCacheEntry;  // NULL if not in cache
     const uint32_t          fUniqueID;
 
     GrResourceKey           fScratchKey;
 
     typedef GrIORef<GrGpuResource> INHERITED;
     friend class GrIORef<GrGpuResource>; // to access notifyIsPurgable.
 };
 
 #endif