New AppListView Scroll Behavior.
The old AppListView did not respond to scroll events from PEEKING mode.
Now the AppListView transitions from PEEKING to FULLSCREEN_ALL_APPS when
a scroll event (mousewheel or touchpad gesture) is received via
AppListView::HandleScroll.
I had to make a fix to ensure that events are properly propogating, and
I had to explicitly pass MouseWheel events from the SearchBoxView
widget.
New Tests:
MouseWheel Scroll events from the SearchBoxView from PEEKING.
MouseWheel scroll events from the AppListView shield from PEEKING.
Ditto, from other states.
BUG=739408
Review-Url: https://codereview.chromium.org/2982453002
Cr-Commit-Position: refs/heads/master@{#487222}
12 files changed
