Fix compilation with GCC-4.8 after r24685

TBR=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/661123002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24701 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/compiler/node-matchers.h

@@ -115,6 +115,7 @@ struct NumericValueMatcher : public NodeMatcher {
         break;
       default:
         has_value_ = false;
+        value_ = 0;  // Make the compiler happy.
         break;
     }
   }