Add /api/v1/notifications/clear, non-existing link cards for statuses will

now return empty hash instead of throwing a 404 error. When following,
merge into timeline will filter statuses

app/assets/javascripts/components/actions/cards.jsx

@@ -9,13 +9,12 @@ export function fetchStatusCard(id) {
     dispatch(fetchStatusCardRequest(id));
 
     api(getState).get(`/api/v1/statuses/${id}/card`).then(response => {
-      dispatch(fetchStatusCardSuccess(id, response.data));
-    }).catch(error => {
-      if (error.response.status === 404) {
-        // This is fine
+      if (response.data.length === 0) {
         return;
       }
 
+      dispatch(fetchStatusCardSuccess(id, response.data));
+    }).catch(error => {
       dispatch(fetchStatusCardFail(id, error));
     });
   };

app/controllers/api/v1/notifications_controller.rb

@@ -24,4 +24,9 @@ class Api::V1::NotificationsController < ApiController
   def show
     @notification = Notification.where(account: current_account).find(params[:id])
   end
+
+  def clear
+    Notification.where(account: current_account).delete_all
+    render_empty
+  end
 end

app/controllers/api/v1/statuses_controller.rb

@@ -22,7 +22,8 @@ class Api::V1::StatusesController < ApiController
   end
 
   def card
-    @card = PreviewCard.find_by!(status: @status)
+    @card = PreviewCard.find_by(status: @status)
+    render_empty if @card.nil?
   end
 
   def reblogged_by

app/lib/feed_manager.rb

@@ -43,6 +43,7 @@ class FeedManager
     timeline_key = key(:home, into_account.id)
 
     from_account.statuses.limit(MAX_ITEMS).each do |status|
+      next if filter?(:home, status, into_account)
       redis.zadd(timeline_key, status.id, status.id)
     end