Add find bar icon to hosted app windows

This CL moves the find icon from LocationBarView into PageActionIconContainerView
enabling the icon to appear in hosted app window title bars.

This change also fixes the find icon getting nudged by
crrev.com/108c0687254683b3beeaa32b6e0a86f2046a867e.

Before 108c0687254683b3beeaa32b6e0a86f2046a867e:
https://bugs.chromium.org/p/chromium/issues/attachment?aid=346964&signed_aid=IuPvufZswamla90tWW5FCg==&inline=1
Before CL:
https://bugs.chromium.org/p/chromium/issues/attachment?aid=346965&signed_aid=Aiy5ATHUK4cWS64MyuRMdQ==&inline=1
After CL:
https://bugs.chromium.org/p/chromium/issues/attachment?aid=346968&signed_aid=DR3vtzLR7tlPH3cEwibshQ==&inline=1

Bug: 788051, 814531
Change-Id: I5fa60cce484bd2553131582fc39e6737da34e967
Reviewed-on: https://chromium-review.googlesource.com/1054908
Commit-Queue: Alan Cutter <alancutter@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#574499}
19 files changed