Implement throttling behavior for LocalStorage mojo messages.

mojo/public/cpp/bindings/lib/multiplex_router.cc

Index: mojo/public/cpp/bindings/lib/multiplex_router.cc
diff --git a/mojo/public/cpp/bindings/lib/multiplex_router.cc b/mojo/public/cpp/bindings/lib/multiplex_router.cc
index 14ea64740756a9377829c23512a2eb1b7b457603..fb4168d1efc585f64e0748b36115454e8b43a540 100644
--- a/mojo/public/cpp/bindings/lib/multiplex_router.cc
+++ b/mojo/public/cpp/bindings/lib/multiplex_router.cc
@@ -285,7 +285,8 @@ MultiplexRouter::MultiplexRouter(
     ScopedMessagePipeHandle message_pipe,
     Config config,
     bool set_interface_id_namesapce_bit,
-    scoped_refptr<base::SingleThreadTaskRunner> runner)
+    scoped_refptr<base::SingleThreadTaskRunner> runner,
+    ClientCallBehavior sync_client_call_behavior)
     : set_interface_id_namespace_bit_(set_interface_id_namesapce_bit),
       task_runner_(runner),
       header_validator_(nullptr),
@@ -301,7 +302,8 @@ MultiplexRouter::MultiplexRouter(
       posted_to_process_tasks_(false),
       encountered_error_(false),
       paused_(false),
-      testing_mode_(false) {
+      testing_mode_(false),
+      sync_client_call_behavior_(sync_client_call_behavior) {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
   if (config == SINGLE_INTERFACE_WITH_SYNC_METHODS ||
@@ -540,7 +542,7 @@ bool MultiplexRouter::Accept(Message* message) {
 
   ClientCallBehavior client_call_behavior =
       connector_.during_sync_handle_watcher_callback()
-          ? ALLOW_DIRECT_CLIENT_CALLS_FOR_SYNC_MESSAGES
+          ? sync_client_call_behavior_
           : ALLOW_DIRECT_CLIENT_CALLS;
 
   bool processed =