Handle tap on intent based search results.

Also fix how icon is loaded. IconResId is specific to the package of the
indexed result. If result comes from external app, icon needs to be
decoded against the external app's package context.

Bug: 33432310
Test: RunSettingsRoboTests
Change-Id: Ia0c53e63be757405dfaeceb2d865e7d8de87c5ee