Merge "Interface for WidgetPickerSearchPipeline." into sc-dev am: 94b622da80

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/13690209

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I5e93b1ca7eac7e33cf2e0c024f6f5c1dbb6eebcd