Enable Looper tracing

Sometimes work that SysUI is doing on the main thread is not visible on
perfetto traces. We should enable the app tracing tag on our looper, to
be able to properly visualize where the workload is coming from.

Test: perfetto trace
Fixes: 223615145
Change-Id: I99e11e986996b070288322f24ce68324e93d17b7
1 file changed