The crashpad_{executable, loadable_module} templates won't have
pre-existing configs lists to modify. Use configs and remove_configs
to merge changes into default configs when using the templates.
Change-Id: Id7c0b1991c9d0ac55022b427feb59df28668b959
Reviewed-on: https://chromium-review.googlesource.com/981778
Reviewed-by: Mark Mentovai <mark@chromium.org>