Revert "Add ability to trace shell transitions"

This reverts commit 6ae3b6c6.

Reason for revert: DroidMonitor-triggered revert due to breakage https://android-build.googleplex.com/builds/quarterdeck?branch=git_master&target=test_suites_arm64&lkgb=8640544&lkbb=8644278&fkbb=8640550, bug b/233875239

Change-Id: I44da4fc6d4f7ae585c122624e5cbe7838cd2a71f