It's kindof silly that ExtQuals has an ASTContext&, and we can use that
space better.  Remove this reference.  To make that work, change some APIs
(most importantly, getDesugaredType()) to take an ASTContext& if they
need to return a QualType.  Simultaneously, diminish the need to return a
QualType by introducing some useful APIs on SplitQualType, which is
just a std::pair<const Type *, Qualifiers>.

llvm-svn: 121478
diff --git a/clang/lib/AST/ASTDiagnostic.cpp b/clang/lib/AST/ASTDiagnostic.cpp
index 321a139..8d5e408 100644
--- a/clang/lib/AST/ASTDiagnostic.cpp
+++ b/clang/lib/AST/ASTDiagnostic.cpp
@@ -101,7 +101,7 @@
                                                 ShouldAKA));
   }
 
-  return QC.apply(QT);
+  return QC.apply(Context, QT);
 }
 
 /// \brief Convert the given type to a string suitable for printing as part of