Clear cached data when we change the composite mode

Previously we would change the composite member, but wouldn't actually
invalidate any of the (many) layers of caching we have. This meant that
the changed composite mode wouldn't actually take effect.

Bug: 1005915
Change-Id: I684ccb5011736edbc8b38cba5d2174095ccff9a6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1815608
Reviewed-by: Kevin Ellis <kevers@chromium.org>
Commit-Queue: Stephen McGruer <smcgruer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#699848}
4 files changed