Infrastructure for temportarily relinquishing GPU resources.

content/common/gpu/gpu_messages.h

Index: content/common/gpu/gpu_messages.h
diff --git a/content/common/gpu/gpu_messages.h b/content/common/gpu/gpu_messages.h
index 839de2d55a966c6ffa14103d08ecc30aee75f7b0..52ab4c07546765bdaa2ef1ddfa837796e5235892 100644
--- a/content/common/gpu/gpu_messages.h
+++ b/content/common/gpu/gpu_messages.h
@@ -301,6 +301,11 @@ IPC_MESSAGE_CONTROL0(GpuMsg_DisableWatchdog)
 // Tells the GPU process that the browser has seen a GPU switch.
 IPC_MESSAGE_CONTROL0(GpuMsg_GpuSwitched)
 
+// Tells the GPU process to delete the default_offscreen surface. It will also
+// close the display and any other resources when the last GL surface is
+// deleted. GPU process will respond with GphHosMsg_ResourcesRelinquished.
+IPC_MESSAGE_CONTROL0(GpuMsg_RelinquishResources)
+
 //------------------------------------------------------------------------------
 // GPU Host Messages
 // These are messages to the browser.
@@ -402,6 +407,9 @@ IPC_MESSAGE_CONTROL1(GpuHostMsg_DidDestroyOffscreenContext,
 IPC_MESSAGE_CONTROL1(GpuHostMsg_GpuMemoryUmaStats,
                      content::GPUMemoryUmaStats /* GPU memory UMA stats */)
 
+// Response to GpuMsg_RelinquishResources.
+IPC_MESSAGE_CONTROL0(GpuHostMsg_ResourcesRelinquished)
+
 //------------------------------------------------------------------------------
 // GPU Channel Messages
 // These are messages from a renderer process to the GPU process.