Update iconloaderlib min_sdk_version to 26. am: e543049272

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/libs/systemui/+/15602014

Change-Id: Ic3985f0532e62e074ff427913c1d450b0f1c5d93
tree: 5b4c37764e65ff784b2c0a7f4dbef3f46635eaef
  1. iconloaderlib/
  2. searchuilib/