Route IPC through browser when creating a viewable command buffer.

The communications path for creating a viewable command buffer used to be directly from the renderer (gpu_channel.cc) to the gpu process (gpu_channel.cc).  This patch makes the browser an intermediary:

- renderer (gpu_channel.cc) makes a synchronous request to the browser (picked up in renderer_message_filter.cc and forwarded to gpu_process_host.cc)

- browser (gpu_process_host.cc) makes an asynchronous request to the gpu process (picked up in gpu_thread.cc and forwarded to gpu_channel.cc) for the command buffer

- gpu process (gpu_thread.cc) sends an ACK with the route_id for the command buffer back to the browser (gpu_process_host.cc)

- browser (gpu_process_host.cc) sends a delayed reply back to the renderer
(gpu_channel_host.cc), which had blocked

There are several motivations for this patch:

- creating an onscreen command buffer requires a window to draw into (which is acquired/locked in the browser); by routing through the browser, we can acquire the get the window beforehand (thereby preventing a deadlock in some other work that I'm doing)

- we can eliminate several separate synchronous IPC messages for obtaining and releasing the window associated with drawing (I've tried to unify the different code paths for Linux, Windows, and Mac)

- in the future, we can have the browser allocate SHM for the command buffer and transfer buffers, allowing us to sandbox the gpu process

BUG=none
TEST=by hand on all 3 platforms, trybots

Review URL: http://codereview.chromium.org/6343006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@72798 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 0 insertions, 21 deletions

diff --git a/chrome/renderer/render_widget_fullscreen_pepper.cc b/chrome/renderer/render_widget_fullscreen_pepper.cc
index c4b2d50..091a190 100644
--- a/chrome/renderer/render_widget_fullscreen_pepper.cc
+++ b/chrome/renderer/render_widget_fullscreen_pepper.cc
@@ -162,9 +162,6 @@ RenderWidgetFullscreenPepper::RenderWidgetFullscreenPepper(
     webkit::ppapi::PluginInstance* plugin)
     : RenderWidgetFullscreen(render_thread, WebKit::WebPopupTypeSelect),
       plugin_(plugin),
-#if defined(OS_MACOSX)
-      plugin_handle_(NULL),
-#endif
       context_(NULL),
       buffer_(0),
       program_(0) {
@@ -267,16 +264,6 @@ void RenderWidgetFullscreenPepper::CreateContext() {
   GpuChannelHost* host = render_thread->EstablishGpuChannelSync();
   if (!host)
     return;
-  gfx::NativeViewId view_id;
-#if !defined(OS_MACOSX)
-  view_id = host_window();
-#else
-  Send(new ViewHostMsg_AllocateFakePluginWindowHandle(
-        routing_id(), true, true, &plugin_handle_));
-  if (!plugin_handle_)
-    return;
-  view_id = static_cast<gfx::NativeViewId>(plugin_handle_);
-#endif
   const int32 attribs[] = {
     ggl::GGL_ALPHA_SIZE, 8,
     ggl::GGL_DEPTH_SIZE, 0,
@@ -287,7 +274,6 @@ void RenderWidgetFullscreenPepper::CreateContext() {
   };
   context_ = ggl::CreateViewContext(
       host,
-      view_id,
       routing_id(),
       "GL_OES_packed_depth_stencil GL_OES_depth24",
       attribs);
@@ -314,13 +300,6 @@ void RenderWidgetFullscreenPepper::DestroyContext() {
     ggl::DestroyContext(context_);
     context_ = NULL;
   }
-#if defined(OS_MACOSX)
-  if (plugin_handle_) {
-    Send(new ViewHostMsg_DestroyFakePluginWindowHandle(routing_id(),
-                                                       plugin_handle_));
-    plugin_handle_ = NULL;
-  }
-#endif
 }
 
 namespace {