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

chrome/browser/media/chrome_webrtc_video_quality_browsertest.cc

Index: chrome/browser/media/chrome_webrtc_video_quality_browsertest.cc
diff --git a/chrome/browser/media/chrome_webrtc_video_quality_browsertest.cc b/chrome/browser/media/chrome_webrtc_video_quality_browsertest.cc
index 83205022ea7755f6483a057546759a8245429cf3..7d1347ed9a6227b686fa8fd561e5552944f5e2b4 100644
--- a/chrome/browser/media/chrome_webrtc_video_quality_browsertest.cc
+++ b/chrome/browser/media/chrome_webrtc_video_quality_browsertest.cc
@@ -107,7 +107,7 @@ class WebRtcVideoQualityBrowserTest : public WebRtcTestBase,
     ASSERT_TRUE(temp_working_dir_.CreateUniqueTempDir());
   }
 
-  void SetUpCommandLine(CommandLine* command_line) override {
+  void SetUpCommandLine(base::CommandLine* command_line) override {
     // Set up the command line option with the expected file name. We will check
     // its existence in HasAllRequiredResources().
     webrtc_reference_video_y4m_ = test::GetReferenceFilesDir()
@@ -166,7 +166,7 @@ class WebRtcVideoQualityBrowserTest : public WebRtcTestBase,
       return false;
     }
 
-    CommandLine converter_command(path_to_converter);
+    base::CommandLine converter_command(path_to_converter);
     converter_command.AppendSwitchPath("--frames_dir", GetWorkingDir());
     converter_command.AppendSwitchPath("--output_file",
                                        captured_video_filename);
@@ -219,7 +219,7 @@ class WebRtcVideoQualityBrowserTest : public WebRtcTestBase,
 
     // Note: don't append switches to this command since it will mess up the
     // -u in the python invocation!
-    CommandLine compare_command(CommandLine::NO_PROGRAM);
+    base::CommandLine compare_command(base::CommandLine::NO_PROGRAM);
     EXPECT_TRUE(GetPythonCommand(&compare_command));
 
     compare_command.AppendArgPath(path_to_compare_script);