[fenix] Close https://github.com/mozilla-mobile/fenix/issues/9827: Support display cutouts

app/src/main/java/org/mozilla/fenix/browser/BaseBrowserFragment.kt

@@ -6,6 +6,7 @@ package org.mozilla.fenix.browser
 
 import android.content.Context
 import android.content.Intent
+import android.os.Build
 import android.os.Bundle
 import android.view.Gravity
 import android.view.LayoutInflater
@@ -436,6 +437,7 @@ abstract class BaseBrowserFragment : Fragment(), UserInteractionHandler, Session
                     sessionManager,
                     SessionUseCases(sessionManager),
                     customTabSessionId,
+                    ::viewportFitChange,
                     ::fullScreenChanged
                 ),
                 owner = this,
@@ -817,6 +819,14 @@ abstract class BaseBrowserFragment : Fragment(), UserInteractionHandler, Session
         pipFeature?.onPictureInPictureModeChanged(enabled)
     }
 
+    private fun viewportFitChange(layoutInDisplayCutoutMode: Int) {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
+            val layoutParams = activity?.window?.attributes
+            layoutParams?.layoutInDisplayCutoutMode = layoutInDisplayCutoutMode
+            activity?.window?.attributes = layoutParams
+        }
+    }
+
     private fun fullScreenChanged(inFullScreen: Boolean) {
         if (inFullScreen) {
             FenixSnackbar.make(