Help GCC along with code that's actually unreachable.

Unfortunately I don't think there's a fix for this that will work upstream and
also satisfy Clang's -Wunreachable-code, which is a pity. But I'll give it some
more thought -perhaps there's some way out.

llvm-svn: 148645

llvm/utils/unittest/googletest/gtest.cc

@@ -2481,6 +2481,9 @@ static const char * TestPartResultTypeToString(TestPartResult::Type type) {
       return "Failure\n";
 #endif
   }
+
+  // All cases return, so this is unreachable but GCC doesn't know it
+  abort();
 }
 
 // Prints a TestPartResult to a String.