Pepper takes ownership of a mailbox before passing it to the texture layer.

gpu/ipc/service/gpu_command_buffer_stub.h

Index: gpu/ipc/service/gpu_command_buffer_stub.h
diff --git a/gpu/ipc/service/gpu_command_buffer_stub.h b/gpu/ipc/service/gpu_command_buffer_stub.h
index 63fb4c750728bf39e3a78d80eac0cf143286a279..3e19854b3f2c99c45df534b9799b7de3199000cb 100644
--- a/gpu/ipc/service/gpu_command_buffer_stub.h
+++ b/gpu/ipc/service/gpu_command_buffer_stub.h
@@ -164,7 +164,10 @@ class GPU_EXPORT GpuCommandBufferStub
   void OnInitialize(base::SharedMemoryHandle shared_state_shm,
                     IPC::Message* reply_message);
   void OnSetGetBuffer(int32_t shm_id, IPC::Message* reply_message);
-  void OnProduceFrontBuffer(const Mailbox& mailbox);
+  void OnTakeFrontBuffer(const Mailbox& mailbox);
+  void OnReturnFrontBuffer(const Mailbox& mailbox,
+                           const SyncToken& sync_token,
+                           bool is_lost);
   void OnGetState(IPC::Message* reply_message);
   void OnWaitForTokenInRange(int32_t start,
                              int32_t end,