Insert module constructors in a module pass

Summary:
If we insert them from function pass some analysis may be missing or invalid.
Fixes PR42877.

Reviewers: eugenis, leonardchan

Reviewed By: leonardchan

Subscribers: hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68832



> llvm-svn: 374481
Signed-off-by: Vitaly Buka <vitalybuka@google.com>

llvm-svn: 374527