Remove experiment percentage for VR tests on K

Removes the experiment percentage from the VR tests on the K CQ bot.
This would make failures blocking, except there was a typo so failures
were already blocking.

Bug: 709620
Change-Id: I8d7727cd92d8e400540f1f9937cf60832ac8e536
Reviewed-on: https://chromium-review.googlesource.com/952334Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541559}

testing/buildbot/chromium.android.json

@@ -2495,7 +2495,6 @@
           "--recover-devices",
           "--shared-prefs-file=//chrome/android/shared_preference_files/test/vr_cardboard_skipdon_setupcomplete.json"
         ],
-        "experiement_percentage": 100,
         "merge": {
           "args": [
             "--bucket",

testing/buildbot/test_suite_exceptions.pyl

@@ -726,7 +726,6 @@
           '--shared-prefs-file=//chrome/android/shared_preference_files/test/vr_cardboard_skipdon_setupcomplete.json',
           '--additional-apk=//third_party/gvr-android-sdk/test-apks/vr_services/vr_services_current.apk',
         ],
-        'experiement_percentage': 100,
         'swarming': {
           'hard_timeout': 1920,
         },