[BlobStorage] Fix IPC race in sending IPC and posting to IO thread

content/child/blob_storage/blob_transport_controller_unittest.cc

Index: content/child/blob_storage/blob_transport_controller_unittest.cc
diff --git a/content/child/blob_storage/blob_transport_controller_unittest.cc b/content/child/blob_storage/blob_transport_controller_unittest.cc
index 08120fcaca7c23a4809d5c3410fbaed9240baf77..79190455f8a6761b4fb14c0e1af39f48d3a685fa 100644
--- a/content/child/blob_storage/blob_transport_controller_unittest.cc
+++ b/content/child/blob_storage/blob_transport_controller_unittest.cc
@@ -281,14 +281,14 @@ TEST_F(BlobTransportControllerTest, TestPublicMethods) {
   EXPECT_TRUE(main_thread_runner_->HasPendingTask());
   // Check that we have the 'store' pending task.
   EXPECT_TRUE(io_thread_runner_->HasPendingTask());
+
+  io_thread_runner_->RunPendingTasks();
   // Check that we've sent the data.
   ExpectRegisterAndStartMessage(kBlobUUID, kBlobContentType,
                                 &message_descriptions);
   main_thread_runner_->ClearPendingTasks();
 
   // Check that we got the correct start message.
-  EXPECT_FALSE(holder->IsTransporting(kBlobUUID));
-  io_thread_runner_->RunPendingTasks();
   EXPECT_TRUE(holder->IsTransporting(kBlobUUID));
   base::Tuple<std::string, std::vector<DataElement>> message_contents;
   EXPECT_EQ(MakeBlobElement(KRefBlobUUID, 10, 10), message_descriptions[0]);