Update ADB icon for Android T.

Bug: 216297617
Test: atest core/tests/coretests/src/android/graphics/drawable/IconTest.java
      (yes technically we are using the adb icon to test
      Icon, but this has the symmetric effect of using Icon
      to test the existence and validity of stat_sys_adb.)
Change-Id: Ief52045b2ffba1e4e0e335e4f77ea230c5d32bbd