Fix misclassified jank for CUJ SHADE_DIALOG_OPEN (and others).

This fix includes two changes:
1. The jank should be measured in and attributed to the opening
   dialog's window, not the origin view's window. This is because
   that's where the animation actually happens.
2. Logging should begin when the animator starts, and not when the
   animation is requested to start, because these two do not happen
   in the same frame.

Bug: 409008342
Flag: com.android.systemui.fix_dialog_launch_animation_jank_logging
Test: atest DialogTransitionAnimatorTest + perfetto
Change-Id: Ia8d338217e2441d3aba0e5b922fb4d1878612cf4