dispatcher: fix test result parsing, build ranges for failure alerts, other fixes

go/src/infra/monitoring/messages/alerts.go

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Package alerts contains structs defined to implement the json format:
 // https://docs.google.com/document/d/10MESGzRy9uAy3Y3-PxUcjiuF3BD3FGGmCNvCjqm3WQQ/preview
 
 package messages
 
 import (
@@ skipping 66 matching lines @@
 // BuildFailure is an Extension.
 type BuildFailure struct {
         TreeCloser       bool
         Builders         []AlertedBuilder
         Reasons          []Reason
         RegressionRanges []RegressionRange `json:"regression_ranges"`
 }
 
 // AlertedBuilder represents an individual builder.
 type AlertedBuilder struct {
-        Name          string
-        URL           string
-        FirstFailure  EpochTime `json:"first_failure"`
-        LatestFailure EpochTime `json:"latest_failure"`
+        Name string
+        URL  string
+        // FirstFailure is the build number of first failure.
+        FirstFailure int64 `json:"first_failure"`
+        // LatestFailure is the build number of latest failure.
+        LatestFailure int64 `json:"latest_failure"`
 }
 
 // Reason contains information about why the Alert was triggered.
 type Reason struct {
         TestName string
         Step     string
         URL      string
 }
 
 // RegressionRange identifies the bounds of the location of a regression.
 type RegressionRange struct {
         Repo      string
         URL       string
         Revisions []string
 }