Update NumTypeBits on Type to match the actual number of used bits.

llvm-svn: 191404

clang/include/clang/AST/Type.h

@@ -1214,7 +1214,7 @@ private:
       return CachedLocalOrUnnamed;
     }
   };
-  enum { NumTypeBits = 19 };
+  enum { NumTypeBits = 18 };
 
 protected:
   // These classes allow subclasses to somewhat cleanly pack bitfields