Log AutofillClient on CompatibilityBridge.onAccessibilityEvent().

This is useful to identify cases where a browser used a trampoline activity to
launch its rendering activity.

Bug: 112584717
Bug: 112690889

Test: adb logcat AutofillManager

Change-Id: I5e58cd8c8dc67ddeed8aa0996233dca9b89cc0d3
(cherry picked from commit 7d4461d1)