Add Dino bday mode to field trial testing config

Bug: 846473
Change-Id: I11e7e6c52cb158c4d2c815cbfab81f0f596317e5
Reviewed-on: https://chromium-review.googlesource.com/1127024
Commit-Queue: Edward Jung <edwardjung@chromium.org>
Reviewed-by: Mark Pearson <mpearson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#577671}

testing/variations/fieldtrial_testing_config.json

@@ -1521,6 +1521,26 @@
             ]
         }
     ],
+    "EnableEasterEggBdayMode": [
+        {
+            "platforms": [
+                "android",
+                "chromeos",
+                "ios",
+                "linux",
+                "mac",
+                "windows"
+            ],
+            "experiments": [
+                {
+                    "name": "enabled",
+                    "enable_features": [
+                        "DinoEasterEggBdayMode"
+                    ]
+                }
+            ]
+        }
+    ],
     "EnableEmojiContextMenu": [
         {
             "platforms": [