Replace context parenting by sharing through mailboxes

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>
 
 #include "base/shared_memory.h"
 #include "content/common/content_export.h"
 #include "content/common/gpu/gpu_memory_allocation.h"
 #include "content/common/gpu/gpu_memory_uma_stats.h"
 #include "content/common/gpu/gpu_process_launch_causes.h"
 #include "content/common/gpu/gpu_rendering_stats.h"
 #include "content/public/common/common_param_traits.h"
 #include "content/public/common/gpu_memory_stats.h"
 #include "gpu/command_buffer/common/command_buffer.h"
 #include "gpu/command_buffer/common/constants.h"
+#include "gpu/command_buffer/common/mailbox.h"
 #include "gpu/config/gpu_info.h"
 #include "gpu/ipc/gpu_command_buffer_traits.h"
 #include "ipc/ipc_channel_handle.h"
 #include "ipc/ipc_message_macros.h"
 #include "media/video/video_decode_accelerator.h"
 #include "ui/base/latency_info.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/size.h"
 #include "ui/gl/gpu_preference.h"
 #include "ui/surface/transport_dib.h"
@@ skipping 457 matching lines @@
 // Returns the shared memory handle for the command buffer mapped to the
 // calling process.
 IPC_SYNC_MESSAGE_ROUTED1_1(GpuCommandBufferMsg_Initialize,
                            base::SharedMemoryHandle /* shared_state */,
                            bool /* result */)
 
 // Sets the shared memory buffer used for commands.
 IPC_SYNC_MESSAGE_ROUTED1_0(GpuCommandBufferMsg_SetGetBuffer,
                            int32 /* shm_id */)
 
-// Sets the parent command buffer. This allows the parent and child to share
-// textures.
-IPC_SYNC_MESSAGE_ROUTED2_1(GpuCommandBufferMsg_SetParent,
-                           int32 /* parent_route_id */,
-                           uint32 /* parent_texture_id */,
-                           bool /* result */)
+// Produces the front buffer into a mailbox. This allows another context to draw
+// the output of this context.
+IPC_MESSAGE_ROUTED1(GpuCommandBufferMsg_ProduceFrontBuffer,
+                    gpu::Mailbox /* mailbox */)
 
 // Get the current state of the command buffer.
 IPC_SYNC_MESSAGE_ROUTED0_1(GpuCommandBufferMsg_GetState,
                            gpu::CommandBuffer::State /* state */)
 
 // Get the current state of the command buffer, as fast as possible.
 IPC_SYNC_MESSAGE_ROUTED0_1(GpuCommandBufferMsg_GetStateFast,
                            gpu::CommandBuffer::State /* state */)
 
 // Asynchronously synchronize the put and get offsets of both processes.
@@ skipping 160 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 */