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

chrome/browser/extensions/convert_web_app_browsertest.cc

Index: chrome/browser/extensions/convert_web_app_browsertest.cc
diff --git a/chrome/browser/extensions/convert_web_app_browsertest.cc b/chrome/browser/extensions/convert_web_app_browsertest.cc
index 0d38ce48e7a16b03e3b46cc42cd3ced39dbcd785..5210ca0f1e96850d9ff429bf1028c45b17845280 100644
--- a/chrome/browser/extensions/convert_web_app_browsertest.cc
+++ b/chrome/browser/extensions/convert_web_app_browsertest.cc
@@ -60,7 +60,8 @@ class ExtensionFromWebAppTest
 IN_PROC_BROWSER_TEST_F(ExtensionFromWebAppTest, DISABLED_Basic) {
 #if defined(OS_WIN) && defined(USE_ASH)
   // Disable this test in Metro+Ash for now (http://crbug.com/262796).
-  if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kAshBrowserTests))
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kAshBrowserTests))
     return;
 #endif