Rename GlobalSynchronization to Locks

Also address some review comments in common_throws relating to
ToStr<InvokeType> and exception detail messages.

Change-Id: Ibf2c0f147689fa236d349bd7f01eed3c2522552b
diff --git a/src/signal_catcher.h b/src/signal_catcher.h
index 11a2c09..e8ac812 100644
--- a/src/signal_catcher.h
+++ b/src/signal_catcher.h
@@ -35,9 +35,9 @@
   explicit SignalCatcher(const std::string& stack_trace_file);
   ~SignalCatcher();
 
-  void HandleSigQuit() LOCKS_EXCLUDED(GlobalSynchronization::mutator_lock_,
-                                      GlobalSynchronization::thread_list_lock_,
-                                      GlobalSynchronization::thread_suspend_count_lock_);
+  void HandleSigQuit() LOCKS_EXCLUDED(Locks::mutator_lock_,
+                                      Locks::thread_list_lock_,
+                                      Locks::thread_suspend_count_lock_);
 
 
  private: