Remove obsolete declaration that broke Windows build.

TBR=hpayer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/440393002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22904 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/types.h

@@ -472,7 +472,6 @@ class TypeImpl : public Config::Base {
   static int ExtendUnion(
       UnionHandle unioned, int current_size, TypeHandle t,
       TypeHandle other, bool is_intersect, Region* region);
-  static int NormalizeUnion(UnionHandle unioned, int current_size, int bitset);
 };