Consolidate GPU buffer implementations

src/gpu/gl/GrGLVertexArray.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrGLVertexArray_DEFINED
 #define GrGLVertexArray_DEFINED
 
 #include "GrTypesPriv.h"
 #include "gl/GrGLDefines.h"
 #include "gl/GrGLTypes.h"
 #include "SkTArray.h"
 
-class GrGLVertexBuffer;
-class GrGLIndexBuffer;
 class GrGLGpu;
 
 /**
  * This sets and tracks the vertex attribute array state. It is used internally by GrGLVertexArray
  * (below) but is separate because it is also used to track the state of vertex array object 0.
  */
 class GrGLAttribArrayState {
 public:
     explicit GrGLAttribArrayState(int arrayCount = 0) {
         this->resize(arrayCount);
@@ skipping 100 matching lines @@
     void invalidateCachedState();
 
 private:
     GrGLuint                fID;
     GrGLAttribArrayState    fAttribArrays;
     GrGLuint                fIndexBufferID;
     bool                    fIndexBufferIDIsValid;
 };
 
 #endif