Reduce overlap of analog clock with smart space.

To reduce overlap, this change biases offset to positive Y so that the
clock remains lower on the screen. Note that this doesn't prevent
overlap. It only helps reduce it.

Bug: 133188468
Test: collected screenshots over accelerated 24 hrs and looked for
overlap.

Change-Id: Ib6bdc19a5c93af2cd5df8400e2fa3106c281acf9

packages/SystemUI/src/com/android/keyguard/clock/ClockLayout.java

@@ -94,7 +94,8 @@ public class ClockLayout extends FrameLayout {
                 getBurnInOffset(mBurnInPreventionOffsetX * 2, true) - mBurnInPreventionOffsetX,
                 mDarkAmount);
         final float offsetY = MathUtils.lerp(0f,
-                getBurnInOffset(mBurnInPreventionOffsetY * 2, false) - mBurnInPreventionOffsetY,
+                getBurnInOffset(mBurnInPreventionOffsetY * 2, false)
+                        - 0.5f * mBurnInPreventionOffsetY,
                 mDarkAmount);
 
         // Put the analog clock in the middle of the screen.