GitLab

Apply layer blur on the layer that has wallpaper, but not the widget
because the solid color is a part of widget's layer.

Bug: 1015886
Test: covered by unittest. Also tested manually with blur change reverted.
Change-Id: Iaf0f2faaa1e92285a3f8b45083027a7fccf0bc59
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1885219Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Commit-Queue: Mitsuru Oshima <oshima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#710141}