Added a unique command buffer ID for command buffers.

ppapi/proxy/ppapi_messages.h

Index: ppapi/proxy/ppapi_messages.h
diff --git a/ppapi/proxy/ppapi_messages.h b/ppapi/proxy/ppapi_messages.h
index 7d49d05a450936e25141b86efbe11ff74996117c..9fcfd4d175c21fc50a7f31852716033883c0618d 100644
--- a/ppapi/proxy/ppapi_messages.h
+++ b/ppapi/proxy/ppapi_messages.h
@@ -61,6 +61,7 @@
 #include "ppapi/proxy/serialized_handle.h"
 #include "ppapi/proxy/serialized_structs.h"
 #include "ppapi/proxy/serialized_var.h"
+#include "ppapi/shared_impl/command_buffer_id_pair.h"
 #include "ppapi/shared_impl/compositor_layer_data.h"
 #include "ppapi/shared_impl/dir_contents.h"
 #include "ppapi/shared_impl/file_growth.h"
@@ -131,6 +132,9 @@ IPC_ENUM_TRAITS(PP_VideoDecoder_Profile)
 IPC_ENUM_TRAITS_MAX_VALUE(PP_VideoFrame_Format, PP_VIDEOFRAME_FORMAT_LAST)
 IPC_ENUM_TRAITS_MAX_VALUE(PP_HardwareAcceleration, PP_HARDWAREACCELERATION_LAST)
 IPC_ENUM_TRAITS_MAX_VALUE(PP_VideoProfile, PP_VIDEOPROFILE_MAX)
+IPC_ENUM_TRAITS_MIN_MAX_VALUE(gpu::CommandBufferNamespace,
+                              gpu::kCommandBufferNamespace_Invalid,
+                              gpu::NUM_COMMAND_BUFFER_NAMESPACES - 1)
 
 IPC_STRUCT_TRAITS_BEGIN(PP_Point)
   IPC_STRUCT_TRAITS_MEMBER(x)
@@ -431,6 +435,11 @@ IPC_STRUCT_TRAITS_BEGIN(ppapi::proxy::SerializedNetworkInfo)
   IPC_STRUCT_TRAITS_MEMBER(mtu)
 IPC_STRUCT_TRAITS_END()
 
+IPC_STRUCT_TRAITS_BEGIN(ppapi::CommandBufferIDPair)
+  IPC_STRUCT_TRAITS_MEMBER(namespace_id)
+  IPC_STRUCT_TRAITS_MEMBER(command_buffer_id)
+IPC_STRUCT_TRAITS_END()
+
 // Only whitelisted switches passed through PpapiNaClPluginArgs.
 // The list of switches can be found in:
 //   components/nacl/browser/nacl_process_host.cc
@@ -897,13 +906,14 @@ IPC_MESSAGE_ROUTED1(PpapiHostMsg_PPBCore_ReleaseResource,
                     ppapi::HostResource)
 
 // PPB_Graphics3D.
-IPC_SYNC_MESSAGE_ROUTED3_3(PpapiHostMsg_PPBGraphics3D_Create,
+IPC_SYNC_MESSAGE_ROUTED3_4(PpapiHostMsg_PPBGraphics3D_Create,
                            PP_Instance /* instance */,
                            ppapi::HostResource /* share_context */,
                            std::vector<int32_t> /* attrib_list */,
                            ppapi::HostResource /* result */,
                            gpu::Capabilities /* capabilities */,
-                           ppapi::proxy::SerializedHandle /* shared_state */)
+                           ppapi::proxy::SerializedHandle /* shared_state */,
+                           ppapi::CommandBufferIDPair /* id_pair */)
 IPC_SYNC_MESSAGE_ROUTED2_0(PpapiHostMsg_PPBGraphics3D_SetGetBuffer,
                            ppapi::HostResource /* context */,
                            int32 /* transfer_buffer_id */)