[fenix] Adding menu configuration for A/A experiment and A/B experiment (https://github.com/mozilla-mobile/fenix/pull/16692)

app/src/main/java/org/mozilla/fenix/experiments/Experiments.kt

@@ -0,0 +1,21 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.fenix.experiments
+
+class Experiments {
+    companion object {
+        const val A_A_NIMBUS_VALIDATION = "fenix-nimbus-validation"
+        const val BOOKMARK_ICON = "fenix-bookmark-list-icon"
+    }
+}
+
+class ExperimentBranch {
+    companion object {
+        const val TREATMENT = "treatment"
+        const val CONTROL = "control"
+        const val A1 = "A1"
+        const val A2 = "A2"
+    }
+}

app/src/main/java/org/mozilla/fenix/home/HomeMenu.kt

@@ -22,6 +22,8 @@ import mozilla.components.concept.sync.AuthType
 import mozilla.components.concept.sync.OAuthAccount
 import mozilla.components.support.ktx.android.content.getColorFromAttr
 import org.mozilla.fenix.R
+import org.mozilla.fenix.experiments.ExperimentBranch
+import org.mozilla.fenix.experiments.Experiments
 import org.mozilla.fenix.ext.components
 import org.mozilla.fenix.ext.settings
 import org.mozilla.fenix.theme.ThemeManager
@@ -96,17 +98,41 @@ class HomeMenu(
             onItemTapped.invoke(Item.WhatsNew)
         }
 
+        val experiments = context.components.analytics.experiments
+        val bookmarksIcon = experiments.getExperimentBranch(Experiments.BOOKMARK_ICON)
+            .let {
+                when (it) {
+                    ExperimentBranch.TREATMENT -> R.drawable.ic_bookmark_list
+                    else -> R.drawable.ic_bookmark_filled
+                }
+            }
+
         val bookmarksItem = BrowserMenuImageText(
             context.getString(R.string.library_bookmarks),
-            R.drawable.ic_bookmark_filled,
+            bookmarksIcon,
             primaryTextColor
         ) {
             onItemTapped.invoke(Item.Bookmarks)
         }
 
+        // We want to validate that the Nimbus experiments library is working, from the android UI
+        // all the way back to the data science backend. We're not testing the user's preference
+        // or response, we're end-to-end testing the experiments platform.
+        // So here, we're running multiple identical branches with the same treatment, and if the
+        // user isn't targeted, then we get still get the same treatment.
+        // The `let` block is degenerate here, but left here so as to document the form of how experiments
+        // are implemented here.
+        val historyIcon = experiments.getExperimentBranch(Experiments.A_A_NIMBUS_VALIDATION)
+            .let {
+                when (it) {
+                    ExperimentBranch.A1 -> R.drawable.ic_history
+                    ExperimentBranch.A2 -> R.drawable.ic_history
+                    else -> R.drawable.ic_history
+                }
+            }
         val historyItem = BrowserMenuImageText(
             context.getString(R.string.library_history),
-            R.drawable.ic_history,
+            historyIcon,
             primaryTextColor
         ) {
             onItemTapped.invoke(Item.History)

app/src/main/res/drawable/ic_bookmark_list.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+        android:autoMirrored="true"
+        android:layout_gravity="center"
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportWidth="24"
+        android:viewportHeight="24">
+    <path
+            android:fillColor="?primaryText"
+            android:pathData="M7,15L7.7,11.2L4.8,8.5C4.4,8 4.4,7.3 4.8,6.9C5,6.7 5.2,6.6 5.5,6.6L9.3,6L11,2.6C11.3,2 12.1,1.8 12.6,2.2C12.8,2.3 12.9,2.4 13,2.6L14.7,6L18.5,6.6C19.1,6.7 19.5,7.3 19.4,7.9C19.4,8.1 19.3,8.4 19.1,8.5L16.3,11.2L17,15C17.1,15.4 16.9,15.8 16.6,16.1C16.4,16.2 16.2,16.3 15.9,16.3C15.7,16.3 15.5,16.3 15.4,16.2L12,14.4L8.6,16.2C8,16.5 7.4,16.2 7.1,15.7C7,15.4 7,15.2 7,15ZM5,16.9C4.4,16.9 4,17.3 4,17.9V18.9C4,20.6 5.3,21.9 7,21.9H17C18.7,21.9 20,20.6 20,18.9V17.9C20,17.3 19.6,16.9 19,16.9C18.4,16.9 18,17.3 18,17.9V18.9C18,19.5 17.6,19.9 17,19.9H7C6.4,19.9 6,19.5 6,18.9V17.9C6,17.3 5.6,16.9 5,16.9Z" />
+</vector>