Fix ShCompileTest.DecimalSepLocale failure.
Fix ShCompileTest.DecimalSepLocale failure.

The test had an additional check to make sure we have coverage on every
platform, but this is unnecessary and requires too much overhead to
maintain a list of good locales for all platforms.

Bug: 941249

Change-Id: I3e6da2ad61453fc385edf5f18101c8cb13ae0503
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1520989
Commit-Queue: Jonah Ryan-Davis <682bdb9e7d8ba359ef169b8db374e7a99d394a46@google.com>
Reviewed-by: Geoff Lang <b6fc25fe0362055230985c05cbfa8adb741ccc0f@chromium.org>
Reviewed-by: Jamie Madill <7e492b4f1c8458024932de3ba475cbf015424c30@chromium.org>

ppy/angle,ppy/angle,ppy/angle,ppy/angle