Add UI Profiling

[sdzhong]

Reference https://docs.sentry.io/platforms/android/profiling/#enabling-manual-lifecycle-ui-profiling

Use

  <!-- Enable UI profiling, adjust in production env. This is evaluated only once per session -->
  <meta-data
    android:name="io.sentry.traces.profiling.session-sample-rate"
    android:value="1.0"
  />
  <meta-data
    android:name="io.sentry.traces.profiling.lifecycle"
    android:value="manual"
  />
  <!-- Enable profiling on app start. The app start profile has to be stopped through Sentry.stopProfiler() -->
  <meta-data
    android:name="io.sentry.traces.profiling.start-on-app-start"
    android:value="true"
  />

to replace

android/app/src/main/AndroidManifest.xml

Lines 70 to 75 in 818da02

	<meta-data
	android:name="io.sentry.traces.profiling.enable"
	android:value="true" />
	<meta-data
	android:name="io.sentry.traces.profiling.sample-rate"
	android:value="1.0" />

[sdzhong]

@stefanosiano , can you confirm we want to make the change with manual mode (android:value="manual"? Or would we use trace mode?

Given we don't have Sentry.profiler.startProfiler nor Sentry.profiler.stopProfiler, I believe we'd use trace mode for now.

[stefanosiano]

yeah, if we want to keep the same behaviour we have currently, we can just use the trace mode

[sdzhong]

Some history of what was attempted in a separate PR #171 (comment)

[sdzhong]

Superceded by #175