Android OOP-D: Enable OOP-D for Android Waterfall

Flips the fieldtrial test config to enable OOP-D for Android bots.

We've worked out all the remaining test failures issues and would like
to turn this on to collect additional data from the perf bots, as well
as to ensure stability while we run our finch trial.

Change-Id: I8b896753b6c64aefa36d355c35c40241ba4f88fd
Reviewed-on: https://chromium-review.googlesource.com/1180574
Commit-Queue: Eric Karl <ericrk@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Cr-Commit-Position: refs/heads/master@{#587250}

testing/variations/fieldtrial_testing_config.json

@@ -4845,7 +4845,8 @@
             "platforms": [
                 "windows",
                 "linux",
-                "mac"
+                "mac",
+                "android"
             ],
             "experiments": [
                 {