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

chrome/browser/translate/translate_browsertest.cc

Index: chrome/browser/translate/translate_browsertest.cc
diff --git a/chrome/browser/translate/translate_browsertest.cc b/chrome/browser/translate/translate_browsertest.cc
index b8cb3d10509314f6bd42c9febd58047b30948606..16860e77344c820011c2124a9a7dc8c78b18cf78 100644
--- a/chrome/browser/translate/translate_browsertest.cc
+++ b/chrome/browser/translate/translate_browsertest.cc
@@ -54,7 +54,7 @@ class TranslateBrowserTest : public InProcessBrowserTest {
                       base::FilePath(kTranslateRoot)),
         infobar_service_(NULL) {}
 
-  void SetUpCommandLine(CommandLine* command_line) override {
+  void SetUpCommandLine(base::CommandLine* command_line) override {
     ASSERT_TRUE(https_server_.Start());
     // Setup alternate security origin for testing in order to allow XHR against
     // local test server. Note that this flag shows a confirm infobar in tests.