ExpandHelper: Improve one finger expanding forced handling
Instead of force returning false if view is null, setup a boolean
to force it with custom views like hover. Cherry-picked from CM.

Also request disallow intercept on drag started.

Original commit: https://github.com/AOSPA/android_frameworks_base/commit/e9570a45660973966f5df6a270f34f7826624f28
ExpandHelper.java codes was already inside

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>