util.py: Add timeout for adb disconnect
aosp-stable: Change with ww22 release

Remove hack_reboot as aosp stable fixes it
Use new method to backup and flash image. Note that build command is
changed from "make" to "make dist"
x64-upstream: Skip a test in ChromeShellTest
x64-upstream: Remove the patch to disable restart of shell as it's fixed
x64-upstream: Rebase to 273751 to include new ndk
x64-upstream: Support arm and arm64 as target arch
x64-upstream: Fix the judgement of target_arch