When trying to get the flutter/packages tests running on AVDs (Android virtual devices) with Android 34 (flutter/packages#4804*), the FileSelectorAndroidTest fails in the Linux_android android_platform_tests_shard_1 master build (example: https://ci.chromium.org/ui/p/flutter/builders/try/Linux_android%20android_platform_tests_shard_1%20master/1750/overview) with an error that has so far not been reproducible (i) locally, (ii) on a Linux virtual machine, and (iii) on a devicelab machine.

Suspected causes are:

• A dialog may be appearing on the emulator causing what the test is searching for to not be found.
• A missing graphical interface

*I've made some test changes in that particular PR, but they shouldn't impact the issue.