Add query only fieldtrial for TranslateRankerModel.

Bug: 646711
Change-Id: I818eccf03f7b963004ee1464ba2504896a8272cf
Reviewed-on: https://chromium-review.googlesource.com/517676Reviewed-by: Alexei Svitkine <asvitkine@chromium.org>
Commit-Queue: Philippe Hamel <hamelphi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#476328}

testing/variations/fieldtrial_testing_config.json

@@ -3184,13 +3184,26 @@
             ],
             "experiments": [
                 {
-                    "name": "Enforcement",
+                    "name": "Query",
                     "params": {
                         "translate-ranker-model-url": "https://www.gstatic.com/chrome/intelligence/assist/ranker/models/translate/2017/03/translate_ranker_model_20170329.pb.bin"
                     },
                     "enable_features": [
+                        "TranslateRankerQuery"
+                    ],
+                    "disable_features": [
                         "TranslateRankerEnforcement"
                     ]
+                },
+                {
+                    "name": "Enforcement",
+                    "params": {
+                        "translate-ranker-model-url": "https://www.gstatic.com/chrome/intelligence/assist/ranker/models/translate/2017/03/translate_ranker_model_20170329.pb.bin"
+                    },
+                    "enable_features": [
+                        "TranslateRankerEnforcement",
+                        "TranslateRankerQuery"
+                    ]
                 }
             ]
         }