minor simplification


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@68011 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseStmt.cpp b/lib/Parse/ParseStmt.cpp
index 3ca2f02..b11ffbe 100644
--- a/lib/Parse/ParseStmt.cpp
+++ b/lib/Parse/ParseStmt.cpp
@@ -959,11 +959,8 @@
     }
 
     // Parse the third part of the for specifier.
-    if (Tok.is(tok::r_paren)) {  // for (...;...;)
-      // no third part.
-    } else {
+    if (Tok.isNot(tok::r_paren))    // for (...;...;)
       ThirdPart = ParseExpression();
-    }
   }
   // Match the ')'.
   SourceLocation RParenLoc = MatchRHSPunctuation(tok::r_paren, LParenLoc);