Merge pull request #2115 from mattermost/plt-1506

PLT-1506 Fixing mentions for inactive browser tabs.

web/react/stores/channel_store.jsx

@@ -308,7 +308,7 @@ ChannelStore.dispatchToken = AppDispatcher.register((payload) => {
         ChannelStore.storeChannels(action.channels);
         ChannelStore.storeChannelMembers(action.members);
         currentId = ChannelStore.getCurrentId();
-        if (currentId) {
+        if (currentId && !document.hidden) {
             ChannelStore.resetCounts(currentId);
         }
         ChannelStore.setUnreadCounts();
@@ -321,7 +321,7 @@ ChannelStore.dispatchToken = AppDispatcher.register((payload) => {
             ChannelStore.pStoreChannelMember(action.member);
         }
         currentId = ChannelStore.getCurrentId();
-        if (currentId) {
+        if (currentId && !document.hidden) {
             ChannelStore.resetCounts(currentId);
         }
         ChannelStore.setUnreadCount(action.channel.id);

web/react/stores/socket_store.jsx

@@ -188,7 +188,9 @@ function handleNewPostEvent(msg, translations) {
 
     // Update channel state
     if (ChannelStore.getCurrentId() === msg.channel_id) {
-        if (window.isActive) {
+        if (document.hidden) {
+            AsyncClient.getChannel(msg.channel_id);
+        } else {
             AsyncClient.updateLastViewedAt();
         }
     } else if (UserStore.getCurrentId() !== msg.user_id || post.type !== Constants.POST_TYPE_JOIN_LEAVE) {