make the view more post view button scroll to the last viewed post

Clover/app/src/main/java/org/floens/chan/core/presenter/ThreadPresenter.java

@@ -319,6 +319,15 @@ public class ThreadPresenter implements ChanLoader.ChanLoaderCallback, PostAdapt
         showPosts();
     }
 
+    public void onNewPostsViewClicked() {
+        Post post = findPostById(loadable.lastViewed);
+        if (post != null) {
+            scrollToPost(post, true);
+        } else {
+            scrollTo(-1, true);
+        }
+    }
+
     public void scrollTo(int displayPosition, boolean smooth) {
         threadPresenterCallback.scrollTo(displayPosition, smooth);
     }

Clover/app/src/main/java/org/floens/chan/ui/layout/ThreadLayout.java

@@ -454,7 +454,7 @@ public class ThreadLayout extends CoordinatorLayout implements ThreadPresenter.T
                     @Override
                     public void onClick(View v) {
                         newPostsNotification = null;
-                        presenter.scrollTo(-1, true);
+                        presenter.onNewPostsViewClicked();
                     }
                 }).show();
                 fixSnackbarText(getContext(), newPostsNotification);