GitLab

Make a shared helper for getting the window type from properties.
Apply properties to the window like the old WindowTreeClient.

Bug: 837695
Change-Id: Icfe1efcddb52b2c3ef9d3ed218e02c105885e230
Reviewed-on: https://chromium-review.googlesource.com/1056349
Commit-Queue: Michael Wasserman <msw@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558209}