Make iOS main() functions normal.

The weird foo_mains are no longer needed when we build with GN.

CQ_INCLUDE_TRYBOTS=skia.primary:Build-Mac-Clang-arm-Debug-iOS

Change-Id: Iae50696741e0dc277d96dda4968a1ae41cb17c8a
Reviewed-on: https://skia-review.googlesource.com/8064
Commit-Queue: Mike Klein <mtklein@chromium.org>
Reviewed-by: Stephan Altmueller <stephana@google.com>
17 files changed