Improve Settings launch performance for normal phones

1. Initialize ActivitEmbedding component only if necessary
2. Early return to avoid executing long execution time operations
  ex: initialize ActivityEmbedding component, feature flag operations

Test: manual - launch settings and profile
Test: run
v2/android-crystalball-eng/health/microbench/startup/firstparty/open-settings
on affacted devices
Test: atest SettingsHomepageActivityTest TopLevelWallpaperPreferenceControllerTest DashboardFeatureProviderImplTest TopLevelSettingsTest TopLevelWallpaperPreferenceControllerTest SearchResultTrampolineTest
Test: atest CtsSettingsTestCases
Fixes: 281505190

Change-Id: I0c1a1dc50f26c4ded02de82190dd7aad59c20c01