[Implicit Modules] Add -cc1 option -fmodules-strict-context-hash which includes search paths and diagnostics.

Differential Revision: https://reviews.llvm.org/D68528

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@375322 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed