Initial support for external sources

app/src/main/java/eu/kanade/tachiyomi/util/ViewExtensions.kt

@@ -21,10 +21,11 @@ fun View.getCoordinates() = Point((left + right) / 2, (top + bottom) / 2)
  * @param length the duration of the snack.
  * @param f a function to execute in the snack, allowing for example to define a custom action.
  */
-inline fun View.snack(message: String, length: Int = Snackbar.LENGTH_LONG, f: Snackbar.() -> Unit) {
+inline fun View.snack(message: String, length: Int = Snackbar.LENGTH_LONG, f: Snackbar.() -> Unit): Snackbar {
     val snack = Snackbar.make(this, message, length)
     val textView = snack.view.findViewById(android.support.design.R.id.snackbar_text) as TextView
     textView.setTextColor(Color.WHITE)
     snack.f()
     snack.show()
+    return snack
 }