Remove a ctor from SkAutoGlyphCache; removal continues.

This change SkAutoGlyphCache with one remaining ctor, then
it's time to remove SkAutoGlyphCacheNoGamma, which is used
but Android.

Change-Id: I0f75ccb4139700d0b678492173f50ac0580d20cd
Reviewed-on: https://skia-review.googlesource.com/115007
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Herb Derby <herb@google.com>
2 files changed