Revert of GrResourceCache2 manages scratch texture.

include/gpu/GrGpuResource.h

Index: include/gpu/GrGpuResource.h
diff --git a/include/gpu/GrGpuResource.h b/include/gpu/GrGpuResource.h
index 17f34d62b2609fc1b641694bdafb0df30c216ce2..61849e7232fd9f23df1219429d7355580a2606ef 100644
--- a/include/gpu/GrGpuResource.h
+++ b/include/gpu/GrGpuResource.h
@@ -49,21 +49,27 @@
     // templated helper classes (e.g. SkAutoTUnref). However, we have different categories of
     // refs (e.g. pending reads). We also don't require thread safety as GrCacheable objects are
     // not intended to cross thread boundaries.
+    // internal_dispose() exists because of GrTexture's reliance on it. It will be removed
+    // soon.
     void ref() const {
-        this->validate();
         ++fRefCnt;
+        // pre-validate once internal_dispose is removed (and therefore 0 ref cnt is not allowed).
+        this->validate();
     }
 
     void unref() const {
         this->validate();
         --fRefCnt;
         if (0 == fRefCnt && 0 == fPendingReads && 0 == fPendingWrites) {
-            SkDELETE(this);
+            this->internal_dispose();
         }
     }
 
-    bool isPurgable() const { return this->reffedOnlyByCache() && !this->internalHasPendingIO(); }
-    bool reffedOnlyByCache() const { return 1 == fRefCnt; }
+    virtual void internal_dispose() const { SkDELETE(this); }
+
+    /** This is exists to service the old mechanism for recycling scratch textures. It will
+        be removed soon. */
+    bool unique() const { return 1 == (fRefCnt + fPendingReads + fPendingWrites); }
 
     void validate() const {
 #ifdef SK_DEBUG
@@ -74,8 +80,9 @@
 #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); }
@@ -91,7 +98,7 @@
         this->validate();
         --fPendingReads;
         if (0 == fRefCnt && 0 == fPendingReads && 0 == fPendingWrites) {
-            SkDELETE(this);
+            this->internal_dispose();
         }
     }
 
@@ -104,7 +111,7 @@
         this->validate();
         --fPendingWrites;
         if (0 == fRefCnt && 0 == fPendingReads && 0 == fPendingWrites) {
-            SkDELETE(this);
+            this->internal_dispose();
         }
     }
 
@@ -115,17 +122,6 @@
 
     // 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.
-
     template <typename, IOType> friend class GrPendingIOResource;
 };