Added UMA stats to track the budget for any service worker which receives a

chrome/browser/push_messaging/background_budget_service_unittest.cc

 // Copyright 2016 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.
 
 #include <stdint.h>
 #include <string>
 
 #include "base/memory/ptr_util.h"
 #include "base/test/simple_test_clock.h"
 #include "chrome/browser/engagement/site_engagement_service.h"
 #include "chrome/browser/push_messaging/background_budget_service.h"
 #include "chrome/browser/push_messaging/background_budget_service_factory.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/test/base/testing_profile.h"
 #include "components/prefs/pref_service.h"
 #include "components/prefs/scoped_user_pref_update.h"
 #include "content/public/test/test_browser_thread_bundle.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
 const char kTestOrigin[] = "https://example.com";
 const double kTestBudget = 10.0;
-const double kTestSES = 24.0;
+const double kTestSES = 48.0;
 const double kLowSES = 1.0;
 const double kMaxSES = 100.0;
 // Mirrors definition in BackgroundBudgetService, this is 10 days of seconds.
 const double kSecondsToAccumulate = 864000.0;
 
 }  // namespace
 
 class BackgroundBudgetServiceTest : public testing::Test {
  public:
   BackgroundBudgetServiceTest() {}
@@ skipping 142 matching lines @@
   double budget = 0.0;
 
   // Measure over 200 hours. In each hour a message is received, and for 1 in
   // 10, budget is consumed.
   for (int i = 0; i < 200; i++) {
     // Query for the budget after 1 hour has passed.
     clock->Advance(base::TimeDelta::FromHours(1));
     budget = service->GetBudget(origin);
 
     if (i % 10 == 0) {
-      service->StoreBudget(origin, budget - 1.0);
+      double newBudget =

[Peter Beverloo, 2016/05/17 11:04:34]

nit: new_budget

[harkness, 2016/05/17 13:08:16]

actually, refactored a bit so renamed the variable.

+          budget - BackgroundBudgetService::GetBackgroundProcessingCost();
+      service->StoreBudget(origin, newBudget);
     }
   }
 
-  // With a SES of 24.0, the origin will get a budget of 2.4 per day, but the
+  // With a SES of 48.0, the origin will get a budget of 2.4 per day, but the
   // old budget will also decay. At the end, we expect the budget to be lower
   // than the starting budget.
   EXPECT_GT(budget, 0.0);
   EXPECT_LT(budget, kTestBudget);
 }
 
 TEST_F(BackgroundBudgetServiceTest, GetBudgetInvalidBudget) {
   const GURL origin(kTestOrigin);
 
   // Set a starting SES for the url.
   SetSiteEngagementScore(origin, kTestSES);
 
   // Set a badly formatted budget in the user preferences.
   DictionaryPrefUpdate update(profile()->GetPrefs(),
                               prefs::kBackgroundBudgetMap);
   base::DictionaryValue* update_map = update.Get();
   update_map->SetStringWithoutPathExpansion(origin.spec(), "20#2.0");
 
   // Get the budget, expect that it will return SES.
   double budget = GetService()->GetBudget(origin);
 
   EXPECT_DOUBLE_EQ(budget, kTestSES);
 }