Log CompatibilityBridge.onAccessibilityEvent()

Altough these are super spammy, they're super valuable when debugging why
compat mode doesn't work.

Bug: 112417431
Fixes: 112584717

Test: adb logcat AutofillManager

Change-Id: I1574b51b1c6caf783038b82ff207986b726b2e8b
(cherry picked from commit 5d35d3d2)