Explicitly list files for the build. Removes shelling out to enumerate_files for the main targets (tests and examples are currently unchanged) in favor of explicitly listing out the files in the build. There are a number of reasons. My immediate reason is that doing this allows the file lists to be shared with the GN build so the GYP and GN builds of angle should mostly automatically stay in sync now. In addition, I don't think we should be enumerating files in GYP. No other Chrome sub-projects do this, and Chrome engineers expect files to be listed in .gyp* files. It's also slower to shell out a bunch of times to get the file lists (this matters more in the GN build which runs very quickly). Updates the GN build to share these file lists. This unbreaks the Windows GN Angle build. BUG=angle:698 Change-Id: Iab8829628aeb7232bb64f4c247c35c6485bba3ee Reviewed-on: https://chromium-review.googlesource.com/208461 Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Brett Wilson <brettw@chromium.org> Reviewed-by: Shannon Woods <shannonwoods@chromium.org>