[Offline Pages] Close race condition of multiple StartProcessing callers.

components/offline_pages/background/request_coordinator_unittest.cc

Index: components/offline_pages/background/request_coordinator_unittest.cc
diff --git a/components/offline_pages/background/request_coordinator_unittest.cc b/components/offline_pages/background/request_coordinator_unittest.cc
index 25c6311e1034c0437c628875ebec7a272b1969b7..633f47968f42a32b3a3d5b30fcad6b894c838047 100644
--- a/components/offline_pages/background/request_coordinator_unittest.cc
+++ b/components/offline_pages/background/request_coordinator_unittest.cc
@@ -190,6 +190,8 @@ class RequestCoordinatorTest
     return coordinator_->is_busy();
   }
 
+  bool is_starting() { return coordinator_->is_starting(); }
+
   // Empty callback function.
   void EmptyCallbackFunction(bool result) {
   }
@@ -601,6 +603,7 @@ TEST_F(RequestCoordinatorTest, StartProcessingThenStopProcessingImmediately) {
           &RequestCoordinatorTest::EmptyCallbackFunction,
           base::Unretained(this));
   EXPECT_TRUE(coordinator()->StartProcessing(device_conditions, callback));
+  EXPECT_TRUE(is_starting());
 
   // Now, quick, before it can do much (we haven't called PumpLoop), cancel it.
   coordinator()->StopProcessing();
@@ -608,6 +611,8 @@ TEST_F(RequestCoordinatorTest, StartProcessingThenStopProcessingImmediately) {
   // Let the async callbacks in the request coordinator run.
   PumpLoop();
 
+  EXPECT_FALSE(is_starting());
+
   // OfflinerDoneCallback will not end up getting called with status SAVED,
   // since we cancelled the event before it called offliner_->LoadAndSave().
   EXPECT_EQ(Offliner::RequestStatus::REQUEST_COORDINATOR_CANCELED,
@@ -638,12 +643,14 @@ TEST_F(RequestCoordinatorTest, StartProcessingThenStopProcessingLater) {
           &RequestCoordinatorTest::EmptyCallbackFunction,
           base::Unretained(this));
   EXPECT_TRUE(coordinator()->StartProcessing(device_conditions, callback));
+  EXPECT_TRUE(is_starting());
 
   // Let all the async parts of the start processing pipeline run to completion.
   PumpLoop();
 
   // Coordinator should now be busy.
   EXPECT_TRUE(is_busy());
+  EXPECT_FALSE(is_starting());
 
   // Now we cancel it while the prerenderer is busy.
   coordinator()->StopProcessing();
@@ -738,6 +745,7 @@ TEST_F(RequestCoordinatorTest, WatchdogTimeout) {
   WaitForCallback();
   PumpLoop();
 
+  EXPECT_FALSE(is_starting());
   EXPECT_TRUE(OfflinerWasCanceled());
   EXPECT_EQ(Offliner::RequestStatus::REQUEST_COORDINATOR_CANCELED,
             last_offlining_status());