Don't display remove log button if it's already removed

assets/scripts/app/models/job.coffee

@@ -132,10 +132,8 @@ require 'travis/model'
   ).property('finishedAt')
 
   canRemoveLog: (->
-    # This should somehow get the status of removed log, but unfortunately there is
-    # no easy way to do that at the moment
-    true
-  ).property()
+    !@get('log.removed')
+  ).property('log.removed')
 
   slug: (->
     "#{@get('repo.slug')} ##{@get('number')}"

assets/scripts/app/models/log.coffee

@@ -39,7 +39,10 @@ require 'travis/log_chunks'
     console.log 'log model: fetching log' if Log.DEBUG
     @clearParts()
     handlers =
-      json: (json) => @loadParts(json['log']['parts'])
+      json: (json) =>
+        if json['log']['removed_at']
+          @set('removed', true)
+        @loadParts(json['log']['parts'])
       text: (text) => @loadText(text)
     Travis.Log.Request.create(id: id, handlers: handlers).run() if id = @get('job.id')