Don't clear mPattern when clearing visual pattern.

This CL ensures that when clearing the lockscreen pattern in
onHandleUp(), we retain mPattern. This fixes a bug that prevents
changing from Pattern to other modalities.

Bug: 77257848
Test: Change from pattern to pin/password

Change-Id: Ied74eafd17939214c62bdd617ecef7a9974f755d
1 file changed