Before this change, only the spinner inside
SettingsSpinnerPreference is clickable. The preference
itself is not clickable.
After this change, whole preference area is clickable
and it will show dropdown view of the spinnner at
onPreferenceClick.
Bug: 187142293
Test: atest SettingsSpinnerPreferenceTest
manual visual
Inserts an USB flash drive and clicks SettingsSpinnerPreference
in Storage Settings.
Change-Id: Ib4de017e6f5930f7b29c8958f2fe7f7dbe347324
e24824b9cc