Two changes to Sema::LookupDecl() interface. 
(1) Remove IdLoc (it's never used). 
(2) Add a bool to enable/disable lazy builtin creaation (defaults to true).

This enables us to use LookupDecl() in Sema::isTypeName(), which is also part of this commit.

To make this work, I changed isTypeName() to be a non-const member function. I'm not happy with this, however I fiddled with making LookupDecl() and friends const and it got ugly pretty quickly. We can certainly add it back if/when someone has time to fiddle with it. For now, I thought this simplification was more important than retaining the const-ness. 



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@49087 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 05926018..9c36c17 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -75,7 +75,7 @@
                                            IdentifierInfo &II,
                                            bool HasTrailingLParen) {
   // Could be enum-constant, value decl, instance variable, etc.
-  Decl *D = LookupDecl(&II, Decl::IDNS_Ordinary, Loc, S);
+  Decl *D = LookupDecl(&II, Decl::IDNS_Ordinary, S);
   
   // If this reference is in an Objective-C method, then ivar lookup happens as
   // well.