Split //ui/gl into //ui/gl + //ui/gi/init.

Refactor //ui/gl to fix Ozone dep problem. This CL is step 1 described
in the associated bug.

BUG=611142
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review-Url: https://codereview.chromium.org/1920163005
Cr-Commit-Position: refs/heads/master@{#393838}
98 files changed