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

chrome/browser/extensions/extension_tabs_apitest.cc

Index: chrome/browser/extensions/extension_tabs_apitest.cc
diff --git a/chrome/browser/extensions/extension_tabs_apitest.cc b/chrome/browser/extensions/extension_tabs_apitest.cc
index 64ba4b4f459aa62f7d1405bb7f6402ad5122e1c3..4709c98c5110c860197028bcab30b2239c77e18d 100644
--- a/chrome/browser/extensions/extension_tabs_apitest.cc
+++ b/chrome/browser/extensions/extension_tabs_apitest.cc
@@ -38,7 +38,7 @@
 class ExtensionApiNewTabTest : public ExtensionApiTest {
  public:
   ExtensionApiNewTabTest() {}
-  void SetUpCommandLine(CommandLine* command_line) override {
+  void SetUpCommandLine(base::CommandLine* command_line) override {
     ExtensionApiTest::SetUpCommandLine(command_line);
     // Override the default which InProcessBrowserTest adds if it doesn't see a
     // homepage.
@@ -165,7 +165,7 @@ class ExtensionApiCaptureTest : public ExtensionApiTest {
     ExtensionApiTest::SetUp();
   }
 
-  void SetUpCommandLine(CommandLine* command_line) override {
+  void SetUpCommandLine(base::CommandLine* command_line) override {
     ExtensionApiTest::SetUpCommandLine(command_line);
   }
 };