Accessibility Service & Shortcut Redesign - Remove “volume key shortcut” setting (5/n)

* AccessibilityShortcutPreferenceFragment was removed,
ShortcutServicePickerFragment should also removed.

Bug: 142529032
Test: Manual test
Change-Id: I08f96a3794235d308b10f3846f1b4f7bb4306923
2 files changed