Don't emit Log.wtf for missing custom view decorator

There are cases where custom view decorator isn't applied - especially
in tests and severely legacy code. Log.wtf in that case will cause jank
and possible issues.

Reduce it to Log.e so we can still track it, but don't do the reporting.

Bug: 430559148
Flag: com.android.server.notification.notification_custom_view_uri_restriction
Test: atest NotificationRowContentBinderImplTest on cf trunk_staging
Change-Id: I0d84649cc83bd82111df3bff4219bf0aab1ebda9