first wave of fixes for @encode sema support.  This is part of PR3648.

The big difference here is that (like string literal) @encode has 
array type, not pointer type.

llvm-svn: 65391
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index bfba598..65a107b 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -153,6 +153,7 @@
   APValue VisitCompoundLiteralExpr(CompoundLiteralExpr *E);
   APValue VisitMemberExpr(MemberExpr *E);
   APValue VisitStringLiteral(StringLiteral *E) { return APValue(E, 0); }
+  APValue VisitObjCEncodeExpr(ObjCEncodeExpr *E) { return APValue(E, 0); }
   APValue VisitArraySubscriptExpr(ArraySubscriptExpr *E);
   APValue VisitUnaryDeref(UnaryOperator *E);
   // FIXME: Missing: __extension__, __real__, __imag__, __builtin_choose_expr