Mus Demo: Add square size parameter to the WindowTreeData constructor

For a demonstration of multiple external windows it is interesting to
have different content drawn in order to distinguish the windows. This
is also useful to distinguish internal VS external mode. This CL adds a
parameter to the WindowTreeData constructor that can be used to specify
the square size in pixels.

BUG=666958
R=rjkroege@chromium.org

Review-Url: https://codereview.chromium.org/2688813003
Cr-Commit-Position: refs/heads/master@{#450030}
1 file changed