Save reader progress when activity is paused (#7121)

(cherry picked from commit f1ab34e27cbd8f26f87e34238af0863d4650b960)

app/src/main/java/eu/kanade/tachiyomi/ui/reader/ReaderActivity.kt

@@ -329,6 +329,11 @@ class ReaderActivity : BaseRxActivity<ReaderPresenter>() {
         super.onSaveInstanceState(outState)
     }
 
+    override fun onPause() {
+        presenter.saveProgress()
+        super.onPause()
+    }
+
     /**
      * Set menu visibility again on activity resume to apply immersive mode again if needed.
      * Helps with rotations.

app/src/main/java/eu/kanade/tachiyomi/ui/reader/ReaderPresenter.kt

@@ -558,6 +558,10 @@ class ReaderPresenter(
         }
     }
 
+    fun saveProgress() {
+        getCurrentChapter()?.let { onChapterChanged(it) }
+    }
+
     /**
      * Called from the activity to preload the given [chapter].
      */