Objective-C keywords are not always identifiers. Some are also C++ keywords

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@60373 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/Lexer.cpp b/lib/Lex/Lexer.cpp
index d72c319..f85cfd9 100644
--- a/lib/Lex/Lexer.cpp
+++ b/lib/Lex/Lexer.cpp
@@ -41,8 +41,9 @@
 
 /// isObjCAtKeyword - Return true if we have an ObjC keyword identifier. 
 bool Token::isObjCAtKeyword(tok::ObjCKeywordKind objcKey) const {
-  return is(tok::identifier) && 
-         getIdentifierInfo()->getObjCKeywordID() == objcKey;
+  if (IdentifierInfo *II = getIdentifierInfo())
+    return II->getObjCKeywordID() == objcKey;
+  return false;
 }
 
 /// getObjCKeywordID - Return the ObjC keyword kind.