Only call TryAnnotateScopeToken when parsing C++.

- This improves -parse-noop of Carbon.h by +2%, and I believe
   compensates for the majority of the performance regression in r58913.

llvm-svn: 60063

clang/lib/Parse/ParseDecl.cpp

@@ -426,7 +426,8 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS) {
 
     // Only annotate C++ scope. Allow class-name as an identifier in case
     // it's a constructor.
-    TryAnnotateScopeToken();
+    if (getLang().CPlusPlus)
+      TryAnnotateScopeToken();
     
     switch (Tok.getKind()) {
     default: