[microsoft] Fix a bug in -fdelayed-template-parsing mode where we were not...

[microsoft] Fix a bug in -fdelayed-template-parsing mode where we were not reentering the delayed function context correctly. The problem was that all template params were reintroduced inside the same scope. So if we had a situation where we had 2 template params with the same name at different scope then clang would generate an error about ambiguous name.

The solution is to create a new ParseScope(Scope::TemplateParamScope) for each template scope that we want to reenter. (from the outmost to the innermost scope)

This fixes some errors when parsing MFC code with clang.

llvm-svn: 140344