Let IPC::SyncMessageFilter take advantage of thread-safe Send.

ppapi/nacl_irt/manifest_service.cc

Index: ppapi/nacl_irt/manifest_service.cc
diff --git a/ppapi/nacl_irt/manifest_service.cc b/ppapi/nacl_irt/manifest_service.cc
index 8a6ec1f641835bae0181f12acb432585a3a8ad62..b98dd3832c850b6200ffc6f141b3a5a7bc908c61 100644
--- a/ppapi/nacl_irt/manifest_service.cc
+++ b/ppapi/nacl_irt/manifest_service.cc
@@ -6,7 +6,7 @@
 
 #include "base/single_thread_task_runner.h"
 #include "ipc/ipc_channel_handle.h"
-#include "ipc/ipc_channel_proxy.h"
+#include "ipc/ipc_sync_channel.h"
 #include "ipc/ipc_sync_message_filter.h"
 #include "native_client/src/trusted/service_runtime/include/sys/errno.h"
 #include "ppapi/nacl_irt/irt_manifest.h"
@@ -21,58 +21,16 @@
 
 namespace ppapi {
 
-// IPC channel is asynchronously set up. So, the NaCl process may try to
-// send a OpenResource message to the host before the connection is
-// established. In such a case, it is necessary to wait for the set up
-// completion.
-class ManifestMessageFilter : public IPC::SyncMessageFilter {
- public:
-  ManifestMessageFilter(base::WaitableEvent* shutdown_event)
-      : SyncMessageFilter(shutdown_event),
-        connected_event_(
-            true /* manual_reset */, false /* initially_signaled */) {
-  }
-
-  bool Send(IPC::Message* message) override {
-    // Wait until set up is actually done.
-    connected_event_.Wait();
-    return SyncMessageFilter::Send(message);
-  }
-
-  // When set up is done, OnFilterAdded is called on IO thread. Unblocks the
-  // Send().
-  void OnFilterAdded(IPC::Sender* sender) override {
-    SyncMessageFilter::OnFilterAdded(sender);
-    connected_event_.Signal();
-  }
-
-  // If an error is found, unblocks the Send(), too, to return an error.
-  void OnChannelError() override {
-    SyncMessageFilter::OnChannelError();
-    connected_event_.Signal();
-  }
-
-  // Similar to OnChannelError, unblocks the Send() on the channel closing.
-  void OnChannelClosing() override {
-    SyncMessageFilter::OnChannelClosing();
-    connected_event_.Signal();
-  }
-
- private:
-  base::WaitableEvent connected_event_;
-
-  DISALLOW_COPY_AND_ASSIGN(ManifestMessageFilter);
-};
-
 ManifestService::ManifestService(
     const IPC::ChannelHandle& handle,
     scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
     base::WaitableEvent* shutdown_event) {
-  filter_ = new ManifestMessageFilter(shutdown_event);
-  channel_ = IPC::ChannelProxy::Create(handle, IPC::Channel::MODE_SERVER,
-                                       NULL,  // Listener
-                                       io_task_runner.get());
-  channel_->AddFilter(filter_.get());
+  channel_ = IPC::SyncChannel::Create(handle, IPC::Channel::MODE_SERVER,
+                                      nullptr /* listener */,
+                                      io_task_runner.get(),
+                                      false /* create_pipe_now */,
+                                      shutdown_event);
+  filter_ = channel_->AddNewSyncMessageFilter();
 }
 
 ManifestService::~ManifestService() {