Change SecurityChips animation behavior on waterfall

The behavior we want to launch is animate-nonsecure-only, so update the
waterfall to that animation behavior.

BUG=

Review-Url: https://codereview.chromium.org/2569433003
Cr-Commit-Position: refs/heads/master@{#437731}

testing/variations/fieldtrial_testing_config.json

@@ -1950,7 +1950,7 @@
                 {
                     "name": "Enabled",
                     "params": {
-                        "animation": "animate-all",
+                        "animation": "animate-nonsecure-only",
                         "visibility": "show-all"
                     },
                     "enable_features": [