3D Compositing in <browser>, first draft.

content/browser/renderer_host/gpu_message_filter.cc

Index: content/browser/renderer_host/gpu_message_filter.cc
diff --git a/content/browser/renderer_host/gpu_message_filter.cc b/content/browser/renderer_host/gpu_message_filter.cc
index 6a06d0af6d193dac9166e7b0f710acfa2b30d95d..8191a69c1a1969f524dedff0432d02eda4f170ca 100644
--- a/content/browser/renderer_host/gpu_message_filter.cc
+++ b/content/browser/renderer_host/gpu_message_filter.cc
@@ -42,11 +42,9 @@ GpuMessageFilter::GpuMessageFilter(int render_process_id,
       weak_ptr_factory_(this) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-#if defined(USE_AURA) || defined(OS_ANDROID)
-  // We use the GPU process for UI on Aura, and we need to share renderer GL
-  // contexts with the compositor context.
+  // We need to share browser plugin parent and child contexts on all
+  // platforms.
   share_contexts_ = true;
-#endif
 }
 
 GpuMessageFilter::~GpuMessageFilter() {