Make callers of CommandLine use it via the base:: namespace.

chrome/browser/download/save_page_browsertest.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/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
@@ skipping 731 matching lines @@
 
   EXPECT_TRUE(base::DieFileDie(full_file_name, false));
   EXPECT_TRUE(base::DieFileDie(dir, true));
 }
 #endif
 
 class SavePageAsMHTMLBrowserTest : public SavePageBrowserTest {
  public:
   SavePageAsMHTMLBrowserTest() {}
   ~SavePageAsMHTMLBrowserTest() override;
-  void SetUpCommandLine(CommandLine* command_line) override {
+  void SetUpCommandLine(base::CommandLine* command_line) override {
     command_line->AppendSwitch(switches::kSavePageAsMHTML);
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SavePageAsMHTMLBrowserTest);
 };
 
 SavePageAsMHTMLBrowserTest::~SavePageAsMHTMLBrowserTest() {
 }
 
@@ skipping 38 matching lines @@
   base::FilePath download_dir = DownloadPrefs::FromDownloadManager(
       GetDownloadManager())->DownloadPath();
   base::FilePath filename = download_dir.AppendASCII("dataurl.txt");
   ASSERT_TRUE(base::PathExists(filename));
   std::string contents;
   EXPECT_TRUE(base::ReadFileToString(filename, &contents));
   EXPECT_EQ("foo", contents);
 }
 
 }  // namespace