Browser Plugin: New Implementation (Browser Side)

content/browser/renderer_host/render_view_host_impl.cc

Index: content/browser/renderer_host/render_view_host_impl.cc
diff --git a/content/browser/renderer_host/render_view_host_impl.cc b/content/browser/renderer_host/render_view_host_impl.cc
index 7613dcfd42b69bf5517ba666fdf81a44d781f3c3..e79d8da86c9832e43a4afda964d9298a905a8926 100644
--- a/content/browser/renderer_host/render_view_host_impl.cc
+++ b/content/browser/renderer_host/render_view_host_impl.cc
@@ -29,6 +29,7 @@
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/browser/renderer_host/render_view_host_delegate.h"
 #include "content/common/accessibility_messages.h"
+#include "content/common/browser_plugin_messages.h"
 #include "content/common/content_constants_internal.h"
 #include "content/common/desktop_notification_messages.h"
 #include "content/common/drag_messages.h"
@@ -827,7 +828,17 @@ bool RenderViewHostImpl::SuddenTerminationAllowed() const {
 // RenderViewHostImpl, IPC message handlers:
 
 bool RenderViewHostImpl::OnMessageReceived(const IPC::Message& msg) {
-  if (!BrowserMessageFilter::CheckCanDispatchOnUI(msg, this))
+  // Allow BrowserPluginHostMsg_* sync messages to run on the UI thread.
+  // Platform apps will not support windowed plugins so the deadlock cycle
+  // browser -> plugin -> renderer -> browser referred in
+  // BrowserMessageFilter::CheckCanDispatchOnUI() is not supposed to happen. If
+  // we want to support windowed plugins, sync messages in BrowserPlugin might
+  // need to be changed to async messages.
+  // TODO(fsamuel): Disallow BrowserPluginHostMsg_* sync messages to run on UI
+  // thread and make these messages async: http://crbug.com/149063.
+  if (msg.type() != BrowserPluginHostMsg_HandleInputEvent::ID &&
+      msg.type() != BrowserPluginHostMsg_ResizeGuest::ID &&
+      !BrowserMessageFilter::CheckCanDispatchOnUI(msg, this))
     return true;
 
   // Filter out most IPC messages if this renderer is swapped out.