Revert of 🏠 Polish bottom sheet content transitions (patchset #1 id:1 of )

Reason for revert:
Appears to be causing multiple chrome_public_test_apk failures on Marshmallow 64 bit Tester.

Original issue's description:
> [Home] Polish bottom sheet content transitions
> This change adds animation when transitioning between bottom sheet
> content. The existing view is faded out completely before the new
> view is faded in. The animation is applied to both the sheet content
> and the toolbar view.
> Notably, the onContentChanged() event is now called when the
> transition animation has finished instead of immediately when
> showContent(...) is called.
> BUG=702717
> Review-Url:
> Cr-Commit-Position: refs/heads/master@{#466780}
> Committed:,
# Not skipping CQ checks because original CL landed more than 1 days ago.

Cr-Commit-Position: refs/heads/master@{#467301}
2 files changed