Fix ADB issues when testing

scripts/avd_test.sh

@@ -131,6 +131,10 @@ test_main() {
   "$sdk" --channel=3 $avd_pkg
   echo no | "$avd" create avd -f -n test -k $avd_pkg
 
+  # Make sure ADB is behaving correctly
+  adb kill-server
+  adb start-server
+
   # Launch stock emulator
   print_title "* Launching $avd_pkg"
   "$emu" @test $emu_args >/dev/null 2>&1 &