Fix QS touches with NSSL migration

On the shade, QQS touches were not properly being sent to the
QuickSettingsCotnroller, as they were incorrectly being seen as the
start of a drag event. Ensure the drag event logic only runs when
actually on the keyguard.

Fixes: 322159446
Test: manual - use shade and QSShade, and interact with QS
Flag: ACONFIG com.android.systemui.keyguard_shade_migration_nssl
DEVELOPMENT

Change-Id: I10cfbbd464e551771e6b49b19bfa2bcf7e10868c