3D Compositing in <browser>, first draft.

ipc/ipc_forwarding_message_filter.cc

Index: ipc/ipc_forwarding_message_filter.cc
diff --git a/ipc/ipc_forwarding_message_filter.cc b/ipc/ipc_forwarding_message_filter.cc
index 48f6e5ff810dbd14fa9afe2f98901098bbb3b986..7bceab7107e580a7ddb301a146978382aafef055 100644
--- a/ipc/ipc_forwarding_message_filter.cc
+++ b/ipc/ipc_forwarding_message_filter.cc
@@ -32,6 +32,12 @@ void ForwardingMessageFilter::RemoveRoute(int routing_id) {
   routes_.erase(routing_id);
 }
 
+void ForwardingMessageFilter::SetPredicate(
+    base::Callback<bool(const Message&)> predicate) {
+  base::AutoLock locked(routes_lock_);
+  predicate_ = predicate;
+}
+
 bool ForwardingMessageFilter::OnMessageReceived(const Message& message) {
   if (message_ids_to_filter_.find(message.type()) ==
       message_ids_to_filter_.end())
@@ -41,6 +47,9 @@ bool ForwardingMessageFilter::OnMessageReceived(const Message& message) {
     base::AutoLock locked(routes_lock_);
     if (routes_.find(message.routing_id()) == routes_.end())
       return false;
+
+    if (!predicate_.is_null() && !predicate_.Run(message))
+      return false;
   }
 
   target_task_runner_->PostTask(