Now that this bot:
https://luci-milo.appspot.com/buildbot/chromium.gpu.fyi/Android%20Release%20%28Nexus%205X%29/?limit=200

is running reliably, and the webgl_conformance_tests are sharded, we should:

1) Put an Android Release (Nexus 5X) on the chromium.gpu waterfall
2) Include it on the bots that master.tryserver.chromium.android:android_n5x_swarming_rel mirrors, similarly to the desktop bots.