Milo: Add an option to hide green steps

milo/appengine/buildbot/build.go

 // Copyright 2016 The LUCI Authors. All rights reserved.
 // Use of this source code is governed under the Apache License, Version 2.0
 // that can be found in the LICENSE file.
 
 package buildbot
 
 import (
         "encoding/json"
         "errors"
         "fmt"
@@ skipping 208 matching lines @@
                         bc.Status = resp.Running
                 } else {
                         if len(step.Results) > 0 {
                                 status := int(step.Results[0].(float64))
                                 bc.Status = result2Status(&status)
                         } else {
                                 bc.Status = resp.Success
                         }
                 }
 
+                // Raise the interesting-ness if the step is not "Success".
+                if bc.Status != resp.Success {
+                        bc.Verbosity = resp.Interesting
+                }
+
                 remainingAliases := stringset.New(len(step.Aliases))
                 for linkAnchor := range step.Aliases {
                         remainingAliases.Add(linkAnchor)
                 }
 
                 getLinksWithAliases := func(logLink *resp.Link, isLog bool) resp.LinkSet {
                         // Generate alias links.
                         var aliases resp.LinkSet
                         if remainingAliases.Del(logLink.Label) {
                                 stepAliases := step.Aliases[logLink.Label]
@@ skipping 399 matching lines @@
         var newAliases map[string][]*buildbotLinkAlias
         if l := remainingAliases.Len(); l > 0 {
                 newAliases = make(map[string][]*buildbotLinkAlias, l)
                 remainingAliases.Iter(func(v string) bool {
                         newAliases[v] = s.Aliases[v]
                         return true
                 })
         }
         s.Aliases = newAliases
 }