Add Resume logic of Purge+Suspend to TabManager.

chrome/browser/memory/tab_manager_web_contents_data_unittest.cc

 // 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.
 
 #include "chrome/browser/memory/tab_manager_web_contents_data.h"
 
 #include "base/test/histogram_tester.h"
 #include "base/test/simple_test_tick_clock.h"
 #include "chrome/test/base/chrome_render_view_host_test_harness.h"
 #include "chrome/test/base/testing_profile.h"
@@ skipping 189 matching lines @@
 
   EXPECT_EQ(1,
             histograms.GetTotalCountsForPrefix(kHistogramName).begin()->second);
 
   histograms.ExpectBucketCount(kHistogramName, 12000, 1);
 }
 
 TEST_F(TabManagerWebContentsDataTest, PurgeAndSuspendState) {
   EXPECT_EQ(TabManager::RUNNING, tab_data()->GetPurgeAndSuspendState());
   base::TimeTicks last_modified = tab_data()->LastPurgeAndSuspendModifiedTime();
+  test_clock().Advance(base::TimeDelta::FromSeconds(5));
   tab_data()->SetPurgeAndSuspendState(TabManager::SUSPENDED);
   EXPECT_EQ(TabManager::SUSPENDED, tab_data()->GetPurgeAndSuspendState());
   EXPECT_GT(tab_data()->LastPurgeAndSuspendModifiedTime(), last_modified);
 
   last_modified = tab_data()->LastPurgeAndSuspendModifiedTime();
+  test_clock().Advance(base::TimeDelta::FromSeconds(5));
   tab_data()->SetPurgeAndSuspendState(TabManager::RESUMED);
   EXPECT_EQ(TabManager::RESUMED, tab_data()->GetPurgeAndSuspendState());
-  EXPECT_GE(tab_data()->LastPurgeAndSuspendModifiedTime(), last_modified);
+  EXPECT_GT(tab_data()->LastPurgeAndSuspendModifiedTime(), last_modified);
 
   last_modified = tab_data()->LastPurgeAndSuspendModifiedTime();
+  test_clock().Advance(base::TimeDelta::FromSeconds(5));
   tab_data()->SetPurgeAndSuspendState(TabManager::RUNNING);
   EXPECT_EQ(TabManager::RUNNING, tab_data()->GetPurgeAndSuspendState());
-  EXPECT_GE(tab_data()->LastPurgeAndSuspendModifiedTime(), last_modified);
+  EXPECT_GT(tab_data()->LastPurgeAndSuspendModifiedTime(), last_modified);
 }
 
 }  // namespace memory