[OfflinePages] Clear busy flag in StopPrerendering() in Request Coordinator.

components/offline_pages/background/request_coordinator_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 "components/offline_pages/background/request_coordinator.h"
 
 #include <memory>
 #include <utility>
 #include <vector>
 
@@ skipping 589 matching lines @@
                                      net::NetworkChangeNotifier::CONNECTION_3G);
   base::Callback<void(bool)> callback =
       base::Bind(
           &RequestCoordinatorTest::EmptyCallbackFunction,
           base::Unretained(this));
   EXPECT_TRUE(coordinator()->StartProcessing(device_conditions, callback));
 
   // Let all the async parts of the start processing pipeline run to completion.
   PumpLoop();
 
+  // Coordinator should now be busy.
+  EXPECT_TRUE(is_busy());
+
   // Now we cancel it while the prerenderer is busy.
   coordinator()->StopProcessing();
 
   // Let the async callbacks in the cancel run.
   PumpLoop();
 
+  EXPECT_FALSE(is_busy());
+
   // OfflinerDoneCallback will not end up getting called with status SAVED,
   // since we cancelled the event before the LoadAndSave completed.
   EXPECT_EQ(Offliner::RequestStatus::REQUEST_COORDINATOR_CANCELED,
             last_offlining_status());
 
   // Since offliner was started, it will have seen cancel call.
   EXPECT_TRUE(OfflinerWasCanceled());
 }
 
 // This tests that canceling a request will result in TryNextRequest() getting
@@ skipping 202 matching lines @@
   PumpLoop();
 
   EXPECT_TRUE(observer().completed_called());
   EXPECT_EQ(RequestCoordinator::SavePageStatus::REMOVED,
             observer().last_status());
   EXPECT_EQ(1UL, last_remove_results().size());
   EXPECT_EQ(kRequestId1, std::get<0>(last_remove_results().at(0)));
 }
 
 }  // namespace offline_pages