From 9b6fd9047d3d6198b2f5c47f4f88f76aa3061c0e Mon Sep 17 00:00:00 2001
From: Arturo Mejia <arturomejiamarmol@gmail.com>
Date: Tue, 28 Jun 2022 15:26:54 -0400
Subject: [PATCH] [fenix] For
 https://github.com/mozilla-mobile/fenix/issues/25213: Add tabs prioritization
 experiment

---
 .experimenter.yaml                                   |  8 ++++++++
 .../main/java/org/mozilla/fenix/components/Core.kt   | 12 +++++++++---
 nimbus.fml.yaml                                      |  8 ++++++++
 3 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/.experimenter.yaml b/.experimenter.yaml
index 0873bd28a4..ad838f3477 100644
--- a/.experimenter.yaml
+++ b/.experimenter.yaml
@@ -7,6 +7,14 @@ default-browser-message:
     message-location:
       type: string
       description: Where is the message to be put.
+engine-settings:
+  description: Contains a set of settings for controlling the web engine configurations.
+  hasExposure: true
+  exposureDescription: ""
+  variables:
+    tabs-prioritization-enabled:
+      type: boolean
+      description: "If true, enables tabs prioritization feature."
 homescreen:
   description: The homescreen that the user goes to when they press home or new tab.
   hasExposure: true
diff --git a/app/src/main/java/org/mozilla/fenix/components/Core.kt b/app/src/main/java/org/mozilla/fenix/components/Core.kt
index cc21ee48a6..c71eebb78b 100644
--- a/app/src/main/java/org/mozilla/fenix/components/Core.kt
+++ b/app/src/main/java/org/mozilla/fenix/components/Core.kt
@@ -88,6 +88,7 @@ import org.mozilla.fenix.historymetadata.DefaultHistoryMetadataService
 import org.mozilla.fenix.historymetadata.HistoryMetadataMiddleware
 import org.mozilla.fenix.historymetadata.HistoryMetadataService
 import org.mozilla.fenix.media.MediaSessionService
+import org.mozilla.fenix.nimbus.FxNimbus
 import org.mozilla.fenix.perf.StrictModeManager
 import org.mozilla.fenix.perf.lazyMonitored
 import org.mozilla.fenix.settings.SupportUtils
@@ -224,6 +225,8 @@ class Core(
      * The [BrowserStore] holds the global [BrowserState].
      */
     val store by lazyMonitored {
+        val tabsPrioritizationEnable =
+            FxNimbus.features.engineSettings.value().tabsPrioritizationEnabled
         val middlewareList =
             mutableListOf(
                 LastAccessMiddleware(),
@@ -244,9 +247,12 @@ class Core(
                 AdsTelemetryMiddleware(adsTelemetry),
                 LastMediaAccessMiddleware(),
                 HistoryMetadataMiddleware(historyMetadataService),
-                SearchTermTabGroupMiddleware(),
-                SessionPrioritizationMiddleware()
-            )
+                SearchTermTabGroupMiddleware()
+            ) + if (tabsPrioritizationEnable) {
+                listOf(SessionPrioritizationMiddleware())
+            } else {
+                emptyList()
+            }
 
         BrowserStore(
             initialState = BrowserState(
diff --git a/nimbus.fml.yaml b/nimbus.fml.yaml
index a6c0aece53..c77994e213 100644
--- a/nimbus.fml.yaml
+++ b/nimbus.fml.yaml
@@ -203,6 +203,14 @@ features:
         value:
           enabled: true
 
+  engine-settings:
+    description: Contains a set of settings for controlling the web engine configurations.
+    variables:
+      tabs-prioritization-enabled:
+        description: If true, enables tabs prioritization feature.
+        type: Boolean
+        default: true
+
 types:
   objects:
     MessageData: