[VK] Fix the animation issue for hiding virtual keyboard.

BUG=330190
TEST=Locally verified in sandbox.

Review URL: https://codereview.chromium.org/120053002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242596 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242596
apps: Stop leaking TestScreen instance.

gfx::Screen::SetScreenInstance() does not take the ownership of the
pointer passed in and thus if the caller does not own the pointer it
created and is passing to Screen, we end up leaking this object.

This changes makes ShellBrowserMainParts own the TestScreen, so we don't
leak and make sure the object is destroyed when ShellBrowserMainParts
goes away.

This should fix leak that was introduced in crrev.com/241880

BUG=None
TEST=app_shell still runs normally and does not crash even more than it
is used to.
R=jamescook@chromium.org
TBR=yoz

Review URL: https://codereview.chromium.org/120583002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242597 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242597