Re-land r92885, which was reverted in r92891.

ppapi/thunk/ppb_graphics_3d_api.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef PPAPI_THUNK_PPB_GRAPHICS_3D_API_H_
 #define PPAPI_THUNK_PPB_GRAPHICS_3D_API_H_
 
 #include "ppapi/c/dev/ppb_graphics_3d_dev.h"
+#include "ppapi/c/dev/ppb_graphics_3d_trusted_dev.h"
 
 namespace ppapi {
 namespace thunk {
 
 class PPB_Graphics3D_API {
  public:
   virtual ~PPB_Graphics3D_API() {}
 
+  // Graphics3D API.
   virtual int32_t GetAttribs(int32_t* attrib_list) = 0;
   virtual int32_t SetAttribs(int32_t* attrib_list) = 0;
   virtual int32_t SwapBuffers(PP_CompletionCallback callback) = 0;
+
+  // Graphics3DTrusted API.
+  virtual PP_Bool InitCommandBuffer(int32_t size) = 0;
+  virtual PP_Bool GetRingBuffer(int* shm_handle,
+                                uint32_t* shm_size) = 0;
+  virtual PP_Graphics3DTrustedState GetState() = 0;
+  virtual int32_t CreateTransferBuffer(uint32_t size) = 0;
+  virtual PP_Bool DestroyTransferBuffer(int32_t id) = 0;
+  virtual PP_Bool GetTransferBuffer(int32_t id,
+                                    int* shm_handle,
+                                    uint32_t* shm_size) = 0;
+  virtual PP_Bool Flush(int32_t put_offset) = 0;
+  virtual PP_Graphics3DTrustedState FlushSync(int32_t put_offset) = 0;
+  virtual PP_Graphics3DTrustedState FlushSyncFast(int32_t put_offset,
+                                                  int32_t last_known_get) = 0;
+
+  // TODO(alokp): Implement GLESChromiumTextureMapping here after
+  // deprecating Context3D.
 };
 
 }  // namespace thunk
 }  // namespace ppapi
 
 #endif  // PPAPI_THUNK_PPB_GRAPHICS_3D_API_H_