This uses the existing dirty bit mDirtyImages to early return in the
TextureD3D::updateStorage methods.

Also fixes a couple missing cases for setting dirty images. The code
could be improved in the future by using a bitset of dirty images per
mip level instead of a single bit.

BUG=angleproject:1392

Change-Id: I58df2be455b6ee51c3e3f76a6fa44ad585d1480d
Reviewed-on: https://chromium-review.googlesource.com/761243Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>