Remove hidden dependency wtfStack

Due to mainline we are not supposed to call hidden APIs
This CL does the following changes:
* `Log.wtfStack` -> `Log.wtf`

Bug: 190443169
Test: None
Tag: #refactor
Change-Id: I92c4345680032572a54adfdd9883876f925d1249
1 file changed
tree: d6a82f6afd7620834d4b6a0567f078bb7d4634c1
  1. android/