This uses the --full argument to work around max path limitations
on Windows. Also includes a couple minor changes for generators
to generate already-formatted code.

Bug: angleproject:2578
Change-Id: I1e400b02e828bfdca21cacb73c649f41226bef55
Reviewed-on: https://chromium-review.googlesource.com/1072161Reviewed-by: Lingfeng Yang <lfy@google.com>
Reviewed-by: Luc Ferron <lucferron@chromium.org>
Reviewed-by: Brandon1 Jones <brandon1.jones@intel.com>
Commit-Queue: Jamie Madill <jmadill@chromium.org>