Update to allow clang to compile in-place build

Also update gitignore for in-place files

BUG=None
TEST=touchtests compiles and runs correctly

Change-Id: Ifdc4c7886005fa91a2665a6078d27b1f1032d188
Reviewed-on: https://chromium-review.googlesource.com/912234
Commit-Ready: Sean O'Brien <seobrien@chromium.org>
Tested-by: Sean O'Brien <seobrien@chromium.org>
Reviewed-by: Andrew de los Reyes <adlr@chromium.org>
3 files changed