Revert of Update mojo sdk to rev c02a28868825edfa57ab77947b8cb15e741c5598

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

Index: third_party/mojo/src/mojo/edk/system/core.h
diff --git a/third_party/mojo/src/mojo/edk/system/core.h b/third_party/mojo/src/mojo/edk/system/core.h
index 4ed5edeedc31a184501543fafca243a9bed22a00..407a06488c8cab60f0273d2ae7ca023230e2840f 100644
--- a/third_party/mojo/src/mojo/edk/system/core.h
+++ b/third_party/mojo/src/mojo/edk/system/core.h
@@ -10,10 +10,10 @@
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/synchronization/lock.h"
 #include "mojo/edk/system/handle_table.h"
 #include "mojo/edk/system/mapping_table.h"
 #include "mojo/edk/system/memory.h"
-#include "mojo/edk/system/mutex.h"
 #include "mojo/edk/system/system_impl_export.h"
 #include "mojo/public/c/system/buffer.h"
 #include "mojo/public/c/system/data_pipe.h"
@@ -175,13 +175,13 @@
 
   embedder::PlatformSupport* const platform_support_;
 
-  // TODO(vtl): |handle_table_mutex_| should be a reader-writer lock (if only we
+  // TODO(vtl): |handle_table_lock_| should be a reader-writer lock (if only we
   // had them).
-  Mutex handle_table_mutex_;
-  HandleTable handle_table_ MOJO_GUARDED_BY(handle_table_mutex_);
+  base::Lock handle_table_lock_;  // Protects |handle_table_|.
+  HandleTable handle_table_;
 
-  Mutex mapping_table_mutex_;
-  MappingTable mapping_table_ MOJO_GUARDED_BY(mapping_table_mutex_);
+  base::Lock mapping_table_lock_;  // Protects |mapping_table_|.
+  MappingTable mapping_table_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(Core);
 };