PLT-3593 fixing issue of removing from team DM list (#3857)

webapp/stores/team_store.jsx

@@ -157,6 +157,19 @@ class TeamStoreClass extends EventEmitter {
         return this.members_for_team;
     }
 
+    hasActiveMemberForTeam(userId) {
+        for (var index in this.members_for_team) {
+            if (this.members_for_team.hasOwnProperty(index)) {
+                if (this.members_for_team[index].user_id === userId &&
+                    this.members_for_team[index].team_id === this.currentTeamId) {
+                    return this.members_for_team[index].delete_at === 0;
+                }
+            }
+        }
+
+        return false;
+    }
+
     saveTeamListings(teams) {
         this.teamListings = teams;
     }