[clang-tidy] run-clang-tidy.py: check if clang-apply-replacements succeeds

Summary:
When running run-clang-tidy.py with -fix it tries to apply found replacements at the end.
If there are errors running clang-apply-replacements, the script currently crashes or displays no error at all.

This patch checks for errors running clang-apply-replacements the same way clang-tidy binary is handled.

Another option would be probably checking for clang-apply-replacements (when -fix is passed) even before running clang-tidy.

Reviewers: Prazek, alexfh, bkramer, mfherbst

Reviewed By: Prazek, alexfh

Subscribers: kimgr, cfe-commits

Tags: #clang-tools-extra

Differential Revision: https://reviews.llvm.org/D32294

llvm-svn: 301365