Merge "[SystemUI] 1.Remove the unnecessary log 2. update signal icon in bg thread" into sc-qpr1-dev am: c3af8564f9 am: 30d2eeaabe

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/16033980

Change-Id: Ida46f092523bf0cd28cc6c5485ae9a35fa6c6755