Make SyncTaskManager's regular Task cancellable (like SyncTask)

chrome/browser/sync_file_system/sync_task_manager_unittest.cc

Index: chrome/browser/sync_file_system/sync_task_manager_unittest.cc
diff --git a/chrome/browser/sync_file_system/sync_task_manager_unittest.cc b/chrome/browser/sync_file_system/sync_task_manager_unittest.cc
index 708da02a5f9ffe3e63422317d03cac898143ca94..95bafd10f473a00bb09a58f419eaf660e9f5245a 100644
--- a/chrome/browser/sync_file_system/sync_task_manager_unittest.cc
+++ b/chrome/browser/sync_file_system/sync_task_manager_unittest.cc
@@ -20,6 +20,15 @@ void IncrementAndAssign(int* counter,
   *status_out = status;
 }
 
+template <typename T>
+void IncrementAndAssignWithOwnedPointer(T* object,
+                                        int* counter,
+                                        SyncStatusCode* status_out,
+                                        SyncStatusCode status) {
+  ++(*counter);
+  *status_out = status;
+}
+
 class TaskManagerClient
     : public SyncTaskManager::Client,
       public base::SupportsWeakPtr<TaskManagerClient> {
@@ -235,4 +244,31 @@ TEST(SyncTaskManagerTest, ScheduleAndCancelSyncTask) {
   EXPECT_FALSE(task_completed);
 }
 
+TEST(SyncTaskManagerTest, ScheduleAndCancelTask) {
+  base::MessageLoop message_loop;
+
+  int callback_count = 0;
+  SyncStatusCode status = SYNC_STATUS_UNKNOWN;
+
+  bool task_started = false;
+  bool task_completed = false;
+
+  {
+    SyncTaskManager task_manager((base::WeakPtr<SyncTaskManager::Client>()));
+    task_manager.Initialize(SYNC_STATUS_OK);
+    MultihopSyncTask* task = new MultihopSyncTask(
+        &task_started, &task_completed);
+    task_manager.ScheduleTask(
+        base::Bind(&MultihopSyncTask::Run, base::Unretained(task)),
+        base::Bind(&IncrementAndAssignWithOwnedPointer<MultihopSyncTask>,
+                   base::Owned(task), &callback_count, &status));
+  }
+
+  message_loop.RunUntilIdle();
+  EXPECT_EQ(0, callback_count);
+  EXPECT_EQ(SYNC_STATUS_UNKNOWN, status);
+  EXPECT_TRUE(task_started);
+  EXPECT_FALSE(task_completed);
+}
+
 }  // namespace sync_file_system