The motivation of this patch is to make sure a user never feel
haptic feedback when scrolling the Emoji palette. In order to
achieve it, EmojiPageKeyboardView#releaseCurrentKey() should
be called whenever (delayed) keydown events should be canceled.
This patch wires up ViewPager.OnPageChangeListener#onPageScrolled
with EmojiPageKeyboardView#releaseCurrentKey() so that delayed
keydown events will be canceled immediately once the ViewParger
starts scrolling.
BUG: 12964092
Change-Id: Iea8c3e090bb16a8622e6b4a850af2bf963aa77d0
4c259866c4