Add find-in-page experiment to fieldtrial_testing_config.json

For FindInPageBestEffortPriority experiment.

Bug: 1063199
Change-Id: I9ca7f639cf4d15937b5dbd024e9a61e606a7a88d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2227713Reviewed-by: Alexander Timin <altimin@chromium.org>
Reviewed-by: Brian White <bcwhite@chromium.org>
Commit-Queue: Rakina Zata Amni <rakina@chromium.org>
Cr-Commit-Position: refs/heads/master@{#774838}

testing/variations/fieldtrial_testing_config.json

@@ -2392,6 +2392,26 @@
             ]
         }
     ],
+    "FindInPageBestEffortPriority": [
+        {
+            "platforms": [
+                "android",
+                "android_weblayer",
+                "chromeos",
+                "linux",
+                "mac",
+                "windows"
+            ],
+            "experiments": [
+                {
+                    "name": "Enabled_20200601",
+                    "enable_features": [
+                        "BlinkSchedulerBestEffortPriorityForFindInPage"
+                    ]
+                }
+            ]
+        }
+    ],
     "FlexNG": [
         {
             "platforms": [