Correctly calculate the newStatusesCount.

Fixes a bug when viewing an updating twkn while logged in.

src/modules/statuses.js

@@ -153,16 +153,18 @@ const addNewStatuses = (state, { statuses, showImmediately = false, timeline, us
       }
     }
 
+    // Decide if we should treat the status as new for this timeline.
+    let resultForCurrentTimeline
     // Some statuses should only be added to the global status repository.
     if (timeline && addToTimeline) {
-      mergeOrAdd(timelineObject.statuses, status)
+      resultForCurrentTimeline = mergeOrAdd(timelineObject.statuses, status)
     }
 
     if (timeline && showImmediately) {
       // Add it directly to the visibleStatuses, don't change
       // newStatusCount
       mergeOrAdd(timelineObject.visibleStatuses, status)
-    } else if (timeline && addToTimeline && result.new) {
+    } else if (timeline && addToTimeline && resultForCurrentTimeline.new) {
       // Just change newStatuscount
       timelineObject.newStatusCount += 1
     }

test/unit/specs/modules/statuses.spec.js

@@ -79,6 +79,24 @@ describe('The Statuses module', () => {
     expect(state.timelines.public.newStatusCount).to.equal(1)
   })
 
+  it('counts the status as new if it has not been seen on this timeline', () => {
+    const state = cloneDeep(defaultState)
+    const status = makeMockStatus({id: 1})
+
+    mutations.addNewStatuses(state, { statuses: [status], timeline: 'public' })
+    mutations.addNewStatuses(state, { statuses: [status], timeline: 'friends' })
+
+    expect(state.allStatuses).to.eql([status])
+    expect(state.timelines.public.statuses).to.eql([status])
+    expect(state.timelines.public.visibleStatuses).to.eql([])
+    expect(state.timelines.public.newStatusCount).to.equal(1)
+
+    expect(state.allStatuses).to.eql([status])
+    expect(state.timelines.friends.statuses).to.eql([status])
+    expect(state.timelines.friends.visibleStatuses).to.eql([])
+    expect(state.timelines.friends.newStatusCount).to.equal(1)
+  })
+
   it('add the statuses to allStatuses if no timeline is given', () => {
     const state = cloneDeep(defaultState)
     const status = makeMockStatus({id: 1})