Thrift: Exception message is protected and accessible to derived classes.

Summary:
Exception message is protected and accessible to derived classes.

Reviewed By: Karl

Revert Plan: revertible

Notes:


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@664971 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/cpp/src/Thrift.h b/lib/cpp/src/Thrift.h
index 6174d46..2268c34 100644
--- a/lib/cpp/src/Thrift.h
+++ b/lib/cpp/src/Thrift.h
@@ -23,7 +23,7 @@
 
   virtual ~TException() throw() {}
 
-  const char* what() const throw() {
+  virtual const char* what() const throw() {
     if (message_.empty()) {
       return "Default TException.";
     } else {
@@ -31,7 +31,7 @@
     }
   }
 
-private:
+protected:
   std::string message_;
 
 };