IPC to generate mailbox names on the GPU process IO thread.

content/common/gpu/gpu_messages.h

 // Copyright (c) 2012 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.
 
 // Multiply-included message file, hence no include guard here, but see below
 // for a much smaller-than-usual include guard section.
 
 #include <string>
 #include <vector>
 
@@ skipping 396 matching lines @@
                             gfx::Size, /* size */
                             GPUCreateCommandBufferConfig, /* init_params */
                             int32 /* route_id */)
 
 // The CommandBufferProxy sends this to the GpuCommandBufferStub in its
 // destructor, so that the stub deletes the actual CommandBufferService
 // object that it's hosting.
 IPC_SYNC_MESSAGE_CONTROL1_0(GpuChannelMsg_DestroyCommandBuffer,
                             int32 /* instance_id */)
 
+// Generates n new unique mailbox names.
+IPC_SYNC_MESSAGE_CONTROL1_1(GpuChannelMsg_GenerateMailboxNames,
+                            unsigned, /* num */
+                            std::vector<std::string> /* mailbox_names */)
 
 #if defined(OS_ANDROID)
 // Register the StreamTextureProxy class with the GPU process, so that
 // the renderer process will get notified whenever a frame becomes available.
 IPC_SYNC_MESSAGE_CONTROL2_1(GpuChannelMsg_RegisterStreamTextureProxy,
                             int32, /* stream_id */
                             gfx::Size, /* initial_size */
                             int /* route_id */)
 
 // Tells the GPU process create and send the java surface texture object to
@@ skipping 248 matching lines @@
 
 // Confirm decoder has been flushed.
 IPC_MESSAGE_ROUTED0(AcceleratedVideoDecoderHostMsg_FlushDone)
 
 // Confirm decoder has been reset.
 IPC_MESSAGE_ROUTED0(AcceleratedVideoDecoderHostMsg_ResetDone)
 
 // Video decoder has encountered an error.
 IPC_MESSAGE_ROUTED1(AcceleratedVideoDecoderHostMsg_ErrorNotification,
                     uint32) /* Error ID */