Avoid copying the data string when posting ImportantFileWriter write tasks

base/files/important_file_writer_unittest.cc

 // Copyright (c) 2012 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 "base/files/important_file_writer.h"
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
@@ skipping 82 matching lines @@
   MessageLoop loop_;
 
  private:
   ScopedTempDir temp_dir_;
 };
 
 TEST_F(ImportantFileWriterTest, Basic) {
   ImportantFileWriter writer(file_, MessageLoopProxy::current().get());
   EXPECT_FALSE(PathExists(writer.path()));
   EXPECT_FALSE(successful_write_observer_.GetAndResetObservationState());
-  writer.WriteNow("foo");
+  writer.WriteNow(make_scoped_ptr(new std::string("foo")));
   RunLoop().RunUntilIdle();
 
   EXPECT_FALSE(successful_write_observer_.GetAndResetObservationState());
   ASSERT_TRUE(PathExists(writer.path()));
   EXPECT_EQ("foo", GetFileContent(writer.path()));
 }
 
 TEST_F(ImportantFileWriterTest, BasicWithSuccessfulWriteObserver) {
   ImportantFileWriter writer(file_, MessageLoopProxy::current().get());
   EXPECT_FALSE(PathExists(writer.path()));
   EXPECT_FALSE(successful_write_observer_.GetAndResetObservationState());
   successful_write_observer_.ObserveNextSuccessfulWrite(&writer);
-  writer.WriteNow("foo");
+  writer.WriteNow(make_scoped_ptr(new std::string("foo")));
   RunLoop().RunUntilIdle();
 
   // Confirm that the observer is invoked.
   EXPECT_TRUE(successful_write_observer_.GetAndResetObservationState());
   ASSERT_TRUE(PathExists(writer.path()));
   EXPECT_EQ("foo", GetFileContent(writer.path()));
 
   // Confirm that re-installing the observer works for another write.
   EXPECT_FALSE(successful_write_observer_.GetAndResetObservationState());
   successful_write_observer_.ObserveNextSuccessfulWrite(&writer);
-  writer.WriteNow("bar");
+  writer.WriteNow(make_scoped_ptr(new std::string("bar")));
   RunLoop().RunUntilIdle();
 
   EXPECT_TRUE(successful_write_observer_.GetAndResetObservationState());
   ASSERT_TRUE(PathExists(writer.path()));
   EXPECT_EQ("bar", GetFileContent(writer.path()));
 
   // Confirm that writing again without re-installing the observer doesn't
   // result in a notification.
   EXPECT_FALSE(successful_write_observer_.GetAndResetObservationState());
-  writer.WriteNow("baz");
+  writer.WriteNow(make_scoped_ptr(new std::string("baz")));
   RunLoop().RunUntilIdle();
 
   EXPECT_FALSE(successful_write_observer_.GetAndResetObservationState());
   ASSERT_TRUE(PathExists(writer.path()));
   EXPECT_EQ("baz", GetFileContent(writer.path()));
 }
 
 TEST_F(ImportantFileWriterTest, ScheduleWrite) {
   ImportantFileWriter writer(file_, MessageLoopProxy::current().get());
   writer.set_commit_interval(TimeDelta::FromMilliseconds(25));
@@ skipping 38 matching lines @@
   MessageLoop::current()->PostDelayedTask(
       FROM_HERE,
       MessageLoop::QuitWhenIdleClosure(),
       TimeDelta::FromMilliseconds(100));
   MessageLoop::current()->Run();
   ASSERT_TRUE(PathExists(writer.path()));
   EXPECT_EQ("baz", GetFileContent(writer.path()));
 }
 
 }  // namespace base