ChromeTabbedActivity.initializeUIWithNative to spread work across tasks

On slow devices this task can take an excessivly long time (over 150ms) and
because the thread is cooperative multitasked it starves more important
work (e.g. navigation tasks). Splitting this up into a number of smaller
tasks (mostly) fixes the problem.

Bug: 863341
Change-Id: Id9b455e7d4188f109b9688e265dcee6cf4c832cb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1615197
Commit-Queue: Alex Clarke <alexclarke@chromium.org>
Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Reviewed-by: Sami Kyöstilä <skyostil@chromium.org>
Reviewed-by: Mohamed Heikal <mheikal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#663245}
3 files changed