[llvm-rc] Add MENU parsing ability (parser, pt 4/8).

This extends llvm-rc parsing tool by MENU resource
(msdn.microsoft.com/en-us/library/windows/desktop/aa381025(v=vs.85).aspx).
As for now, MENUEX
(msdn.microsoft.com/en-us/library/windows/desktop/aa381023(v=vs.85).aspx)
seems unnecessary.

Thanks for Nico Weber for his original work in this area.

Differential Revision: https://reviews.llvm.org/D36898

llvm-svn: 311956
diff --git a/llvm/tools/llvm-rc/ResourceScriptParser.h b/llvm/tools/llvm-rc/ResourceScriptParser.h
index e286f83..3fd1c27 100644
--- a/llvm/tools/llvm-rc/ResourceScriptParser.h
+++ b/llvm/tools/llvm-rc/ResourceScriptParser.h
@@ -130,8 +130,12 @@
   ParseType parseCursorResource();
   ParseType parseIconResource();
   ParseType parseHTMLResource();
+  ParseType parseMenuResource();
   ParseType parseStringTableResource();
 
+  // Helper MENU parser.
+  Expected<MenuDefinitionList> parseMenuItemsList();
+
   // Optional statement parsers.
   ParseOptionType parseLanguageStmt();
   ParseOptionType parseCharacteristicsStmt();