Revert of Update mojo sdk to rev c02a28868825edfa57ab77947b8cb15e741c5598

third_party/mojo/src/mojo/edk/system/endpoint_relayer.h

Index: third_party/mojo/src/mojo/edk/system/endpoint_relayer.h
diff --git a/third_party/mojo/src/mojo/edk/system/endpoint_relayer.h b/third_party/mojo/src/mojo/edk/system/endpoint_relayer.h
index cfeda2405ea19d309aaf0b8609c51e25e0c16bad..8b17a50b78c85343051f338c8821dfe6429d135c 100644
--- a/third_party/mojo/src/mojo/edk/system/endpoint_relayer.h
+++ b/third_party/mojo/src/mojo/edk/system/endpoint_relayer.h
@@ -7,8 +7,8 @@
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/synchronization/lock.h"
 #include "mojo/edk/system/channel_endpoint_client.h"
-#include "mojo/edk/system/mutex.h"
 #include "mojo/edk/system/system_impl_export.h"
 #include "mojo/public/cpp/system/macros.h"
 
@@ -68,8 +68,7 @@
   static unsigned GetPeerPort(unsigned port);
 
   // Initialize this object. This must be called before any other method.
-  void Init(ChannelEndpoint* endpoint0,
-            ChannelEndpoint* endpoint1) MOJO_NOT_THREAD_SAFE;
+  void Init(ChannelEndpoint* endpoint0, ChannelEndpoint* endpoint1);
 
   // Sets (or resets) the filter, which can (optionally) handle/filter
   // |Type::ENDPOINT_CLIENT| messages (see |Filter| above).
@@ -82,9 +81,11 @@
  private:
   ~EndpointRelayer() override;
 
-  Mutex mutex_;
-  scoped_refptr<ChannelEndpoint> endpoints_[2] MOJO_GUARDED_BY(mutex_);
-  scoped_ptr<Filter> filter_ MOJO_GUARDED_BY(mutex_);
+  // TODO(vtl): We could probably get away without the lock if we had a
+  // thread-safe |scoped_refptr|.
+  base::Lock lock_;  // Protects the following members.
+  scoped_refptr<ChannelEndpoint> endpoints_[2];
+  scoped_ptr<Filter> filter_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(EndpointRelayer);
 };