Bug 1830768 - Add nimbus flag for toolbar position

(cherry picked from commit e3d2b97b25d43f36e6ade33482de584a4973ffbc)

app/.experimenter.yaml

@@ -147,6 +147,14 @@ search-term-groups:
     enabled:
       type: boolean
       description: "If true, the feature shows up on the homescreen and on the new tab screen."
+toolbar:
+  description: The searchbar/awesomebar that user uses to search.
+  hasExposure: true
+  exposureDescription: ""
+  variables:
+    toolbar-position-top:
+      type: boolean
+      description: "If true, toolbar appears at top of the screen."
 unified-search:
   description: A feature allowing user to easily search for specified results directly in the search bar.
   hasExposure: true

app/nimbus.fml.yaml

@@ -142,6 +142,13 @@ import:
         }
 
 features:
+  toolbar:
+    description: The searchbar/awesomebar that user uses to search.
+    variables:
+      toolbar-position-top:
+        description: If true, toolbar appears at top of the screen.
+        type: Boolean
+        default: false
   homescreen:
     description: The homescreen that the user goes to when they press home or new tab.
     variables:

app/src/main/java/org/mozilla/fenix/utils/Settings.kt

@@ -887,8 +887,7 @@ class Settings(private val appContext: Context) : PreferencesHolder {
 
     var shouldUseBottomToolbar by booleanPreference(
         appContext.getPreferenceKey(R.string.pref_key_toolbar_bottom),
-        // Default accessibility users to top toolbar
-        default = !touchExplorationIsEnabled && !switchServiceIsEnabled,
+        default = shouldDefaultToBottomToolbar(),
     )
 
     val toolbarPosition: ToolbarPosition
@@ -926,6 +925,18 @@ class Settings(private val appContext: Context) : PreferencesHolder {
             return touchExplorationIsEnabled || switchServiceIsEnabled
         }
 
+    val toolbarPositionTop: Boolean
+        get() = FxNimbus.features.toolbar.value().toolbarPositionTop
+
+    /**
+     * Checks if we should default to bottom toolbar.
+     */
+    fun shouldDefaultToBottomToolbar(): Boolean {
+        // Default accessibility users to top toolbar
+        return (!touchExplorationIsEnabled && !switchServiceIsEnabled) &&
+            !toolbarPositionTop
+    }
+
     fun getDeleteDataOnQuit(type: DeleteBrowsingDataOnQuitType): Boolean =
         preferences.getBoolean(type.getPreferenceKey(appContext), false)
 

app/src/test/java/org/mozilla/fenix/utils/SettingsTest.kt

@@ -878,6 +878,15 @@ class SettingsTest {
         assertTrue(actual)
     }
 
+    @Test
+    fun `GIVEN toolbarPositionTop is false, touchExplorationIsEnabled is true THEN shouldDefaultToBottomToolbar returns false`() {
+        val settings = spyk(settings)
+        every { settings.toolbarPositionTop } returns true
+        every { settings.touchExplorationIsEnabled } returns true
+
+        assertEquals(false, settings.shouldDefaultToBottomToolbar())
+    }
+
     @Test
     fun `GIVEN Https-only mode is disabled THEN the engine mode is HttpsOnlyMode#DISABLED`() {
         settings.shouldUseHttpsOnly = false