Fix memory leak which due to GalleryView.onDetachFromRootInternal not called

app/src/main/java/com/hippo/ehviewer/ui/GalleryActivity.java

@@ -351,24 +351,6 @@ public class GalleryActivity extends EhActivity
         SimpleHandler.getInstance().removeCallbacks(mHideSliderRunnable);
     }
 
-    @Override
-    protected void onPause() {
-        super.onPause();
-
-        if (null != mGalleryView) {
-            mGalleryView.pause();
-        }
-    }
-
-    @Override
-    protected void onResume() {
-        super.onResume();
-
-        if (null != mGalleryView) {
-            mGalleryView.resume();
-        }
-    }
-
     @Override
     public void onWindowFocusChanged(boolean hasFocus) {
         super.onWindowFocusChanged(hasFocus);