Rewrite std::string("") to std::string(), Linux edition.

content/browser/download/download_manager_impl_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 <set>
 #include <string>
 
 #include "base/bind.h"
 #include "base/file_util.h"
 #include "base/files/scoped_temp_dir.h"
@@ skipping 151 matching lines @@
   MOCK_CONST_METHOD0(GetLastModifiedTime, const std::string&());
   MOCK_CONST_METHOD0(GetETag, const std::string&());
   MOCK_CONST_METHOD0(GetLastReason, DownloadInterruptReason());
   MOCK_CONST_METHOD0(GetBrowserContext, BrowserContext*());
   MOCK_CONST_METHOD0(GetWebContents, WebContents*());
   MOCK_CONST_METHOD0(GetFileNameToReportUser, base::FilePath());
   MOCK_METHOD1(SetDisplayName, void(const base::FilePath&));
   MOCK_CONST_METHOD0(GetUserVerifiedFilePath, base::FilePath());
   MOCK_METHOD0(NotifyRemoved, void());
   // May be called when vlog is on.
-  virtual std::string DebugString(bool verbose) const OVERRIDE { return ""; }
+  virtual std::string DebugString(bool verbose) const OVERRIDE {
+    return std::string();
+  }
 };
 
 class MockDownloadManagerDelegate : public DownloadManagerDelegate {
  public:
   MockDownloadManagerDelegate();
   virtual ~MockDownloadManagerDelegate();
 
   MOCK_METHOD0(Shutdown, void());
   MOCK_METHOD0(GetNextId, DownloadId());
   MOCK_METHOD2(DetermineDownloadTarget,
@@ skipping 497 matching lines @@
       .WillOnce(Return());
   EXPECT_CALL(GetMockDownloadItem(3), Remove())
       .Times(0);
 
   download_manager_->RemoveAllDownloads();
   // Because we're mocking the download item, the Remove call doesn't
   // result in them being removed from the DownloadManager list.
 }
 
 }  // namespace content