[AA+] Add QueryLength to DeviceSearchResultContainer. am: 43b1d40918

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/13486574

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: If62667485bfc6b92e8db9f0455027f410c1b0274