C++ Thrift coding style changes

Summary: Make underscore for class members consistent


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@664818 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/cpp/src/concurrency/Mutex.h b/lib/cpp/src/concurrency/Mutex.h
index 9eceb49..de52bbd 100644
--- a/lib/cpp/src/concurrency/Mutex.h
+++ b/lib/cpp/src/concurrency/Mutex.h
@@ -18,20 +18,20 @@
 
  private:
   class impl;
-  impl* _impl;
+  impl* impl_;
 };
 
 class MutexMonitor {
  public: 
-  MutexMonitor(const Mutex& value) : _mutex(value) {
-    _mutex.lock();
+  MutexMonitor(const Mutex& value) : mutex_(value) {
+    mutex_.lock();
   }
   ~MutexMonitor() {
-    _mutex.unlock();
+    mutex_.unlock();
   }
 
  private:
-  const Mutex& _mutex;
+  const Mutex& mutex_;
 };