Convert some more |base::Lock|s to |mojo::system::Mutex|s.

mojo/edk/system/test_channel_endpoint_client.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MOJO_EDK_SYSTEM_TEST_CHANNEL_ENDPOINT_CLIENT_H_
 #define MOJO_EDK_SYSTEM_TEST_CHANNEL_ENDPOINT_CLIENT_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/synchronization/lock.h"
 #include "mojo/edk/system/channel_endpoint.h"
 #include "mojo/edk/system/channel_endpoint_client.h"
 #include "mojo/edk/system/message_in_transit_queue.h"
+#include "mojo/edk/system/mutex.h"
 #include "mojo/public/cpp/system/macros.h"
 
 namespace base {
 class WaitableEvent;
 }
 
 namespace mojo {
 namespace system {
 namespace test {
 
@@ skipping 18 matching lines @@
   // until this object is destroyed or the read event is reset to null.)
   void SetReadEvent(base::WaitableEvent* read_event);
 
   // |ChannelEndpointClient| implementation:
   bool OnReadMessage(unsigned port, MessageInTransit* message) override;
   void OnDetachFromChannel(unsigned port) override;
 
  private:
   ~TestChannelEndpointClient() override;
 
-  mutable base::Lock lock_;  // Protects the members below.
+  mutable Mutex mutex_;
 
-  unsigned port_;
-  scoped_refptr<ChannelEndpoint> endpoint_;
+  unsigned port_ MOJO_GUARDED_BY(mutex_);
+  scoped_refptr<ChannelEndpoint> endpoint_ MOJO_GUARDED_BY(mutex_);
 
-  MessageInTransitQueue messages_;
+  MessageInTransitQueue messages_ MOJO_GUARDED_BY(mutex_);
 
   // Event to trigger if we read a message (may be null).
-  base::WaitableEvent* read_event_;
+  base::WaitableEvent* read_event_ MOJO_GUARDED_BY(mutex_);
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(TestChannelEndpointClient);
 };
 
 }  // namespace test
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_EDK_SYSTEM_TEST_CHANNEL_ENDPOINT_CLIENT_H_