Provide isConst/Volatile on CXXMethodDecl.

This also provides isConst/Volatile/Restrict on FunctionTypes to coalesce
the implementation with other callers (& update those other callers).

Patch contributed by Sam Panzer (panzer@google.com).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@161647 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/DumpXML.cpp b/lib/AST/DumpXML.cpp
index ad551cc..c1432b5 100644
--- a/lib/AST/DumpXML.cpp
+++ b/lib/AST/DumpXML.cpp
@@ -971,9 +971,9 @@
   }
 
   void visitFunctionProtoTypeAttrs(FunctionProtoType *T) {
-    setFlag("const", T->getTypeQuals() & Qualifiers::Const);
-    setFlag("volatile", T->getTypeQuals() & Qualifiers::Volatile);
-    setFlag("restrict", T->getTypeQuals() & Qualifiers::Restrict);
+    setFlag("const", T->isConst());
+    setFlag("volatile", T->isVolatile());
+    setFlag("restrict", T->isRestrict());
   }
   void visitFunctionProtoTypeChildren(FunctionProtoType *T) {
     push("parameters");