Bug 1752919: Make tiled images respect opacity applied as color. r=gw
Bug 1752919: Make tiled images respect opacity applied as color. r=gw

This eliminates the need to determine when WebRender will apply opacity without a
filter, since it will now always apply opacity correctly for both tiled and untiled
images.

Differential Revision: https://phabricator.services.mozilla.com/D147102

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/792208df66b2bdfd5f02a5212935f28df0512fe2

servo/webrender,servo/webrender,servo/webrender,servo/webrender,servo/webrender,servo/webrender