Remove problematic GrContext thread local instance counting

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 32 matching lines @@
 
 class SK_API GrContext : public SkRefCnt {
 public:
     SK_DECLARE_INST_COUNT(GrContext)
 
     /**
      * Creates a GrContext for a backend context.
      */
     static GrContext* Create(GrBackend, GrBackendContext);
 
-    /**
-     * Returns the number of GrContext instances for the current thread.
-     */
-    static int GetThreadInstanceCount();
-
     virtual ~GrContext();
 
     /**
      * The GrContext normally assumes that no outsider is setting state
      * within the underlying 3D API's context/device/whatever. This call informs
      * the context that the state was modified and it should resend. Shouldn't
      * be called frequently for good performance.
      * The flag bits, state, is dpendent on which backend is used by the
      * context, either GL or D3D (possible in future).
      */
@@ skipping 974 matching lines @@
     }
 
     GrTexture* texture() { return fTexture; }
 
 private:
     GrContext*                    fContext;
     GrTexture*                    fTexture;
 };
 
 #endif