Remove destruction-only TearDown() methods in Drive related test.

chrome/browser/chromeos/drive/file_system/move_operation_unittest.cc

 // Copyright 2013 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/chromeos/drive/file_system/move_operation.h"
 
 #include "chrome/browser/chromeos/drive/file_system/operation_test_base.h"
 #include "chrome/browser/google_apis/test_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace drive {
 namespace file_system {
 
 class MoveOperationTest : public OperationTestBase {
  protected:
   virtual void SetUp() OVERRIDE {
    OperationTestBase::SetUp();
    operation_.reset(new MoveOperation(observer(), scheduler(), metadata()));
  }
 
- virtual void TearDown() OVERRIDE {
-   operation_.reset();
-   OperationTestBase::TearDown();
- }
-
  scoped_ptr<MoveOperation> operation_;
 };
 
 TEST_F(MoveOperationTest, MoveFileInSameDirectory) {
   const base::FilePath src_path(
       FILE_PATH_LITERAL("drive/root/Directory 1/SubDirectory File 1.txt"));
   const base::FilePath dest_path(
       FILE_PATH_LITERAL("drive/root/Directory 1/Test.log"));
 
   ResourceEntry src_entry, dest_entry;
@@ skipping 168 matching lines @@
   google_apis::test_util::RunBlockingPoolTask();
   EXPECT_EQ(FILE_ERROR_NOT_A_DIRECTORY, error);
 
   ResourceEntry entry;
   EXPECT_EQ(FILE_ERROR_OK, GetLocalResourceEntry(src_path, &entry));
   EXPECT_EQ(FILE_ERROR_NOT_FOUND, GetLocalResourceEntry(dest_path, &entry));
 }
 
 }  // namespace file_system
 }  // namespace drive