Objective-C SDK modernization. import Foundation even
when a previous definition of NS_OPTION is available
; e.g. from a pch. enhancement to rdar://18498550


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219448 91177308-0d34-0410-b5e6-96231b3b80d8
Fix completion logic to allow for heterogeneous argument types in matcher overloads.

Summary:
There was an assumption that there were no matchers that were overloaded
on matchers and other types of arguments.
This assumption was broken recently with the addition of new matcher
overloads.

Fixes http://llvm.org/PR21226

Reviewers: pcc

Subscribers: klimek, cfe-commits

Differential Revision: http://reviews.llvm.org/D5711

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219450 91177308-0d34-0410-b5e6-96231b3b80d8