[NTP Favicons] Add testing config for two features for fetching icons.

testing/variations/fieldtrial_testing_config.json

Index: testing/variations/fieldtrial_testing_config.json
diff --git a/testing/variations/fieldtrial_testing_config.json b/testing/variations/fieldtrial_testing_config.json
index cda41499917b11d98386d11004ddc8677d613fdf..fe3a793277b3b269eca349fd0382d1948082fde2 100644
--- a/testing/variations/fieldtrial_testing_config.json
+++ b/testing/variations/fieldtrial_testing_config.json
@@ -1537,6 +1537,21 @@
             ]
         }
     ],
+    "NTPFaviconsFromNewServer": [
+        {
+            "platforms": [
+                "android"
+            ],
+            "experiments": [
+                {
+                    "name": "Enabled",
+                    "enable_features": [
+                        "ContentSuggestionsFaviconsFromNewServer"
+                    ]
+                }
+            ]
+        }
+    ],
     "NTPLaunchAfterInactivity": [
         {
             "platforms": [
@@ -1555,6 +1570,22 @@
             ]
         }
     ],
+    "NTPMostLikelyFaviconsFromServer": [
+        {
+            "platforms": [
+                "android",
+                "ios"
+            ],
+            "experiments": [
+                {
+                    "name": "Enabled",
+                    "enable_features": [
+                        "NTPMostLikelyFaviconsFromServer"
+                    ]
+                }
+            ]
+        }
+    ],
     "NTPPersonalizedSectionRanking": [
         {
             "platforms": [