talkback: The "+" menu FAB should be spoken as "Add or upload"

src/main/res/layout/list_fragment.xml

@@ -56,6 +56,7 @@
         android:layout_marginBottom="@dimen/standard_margin"
         android:layout_marginEnd="@dimen/standard_margin"
         android:layout_marginRight="@dimen/standard_margin"
+        android:contentDescription="@string/fab_label"
         android:visibility="gone" />
 
     <android.support.design.widget.BottomNavigationView

src/main/res/values/strings.xml

@@ -827,4 +827,5 @@
     <string name="stream_not_possible_message">Please download media instead or use external app.</string>
     <string name="folder_already_exists">Folder already exists</string>
     <string name="notification_icon">Notification icon</string>
+    <string name="fab_label">Add or upload</string>
 </resources>