delete nullptr,0 section of style guide

The nullptr/0 distinction should go without saying,
and I think worrying about any of the rest just burns brainpower.

Change-Id: I7d0aea300f114e512437c3820f4e80a1408575c1
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/312472
Reviewed-by: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
1 file changed