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

content/zygote/zygote_main_linux.cc

Index: content/zygote/zygote_main_linux.cc
diff --git a/content/zygote/zygote_main_linux.cc b/content/zygote/zygote_main_linux.cc
index 3dc64ecd371410a5147e613db39b816b72b76c24..514891e26f0931d5a04638d2020fbd0852506377 100644
--- a/content/zygote/zygote_main_linux.cc
+++ b/content/zygote/zygote_main_linux.cc
@@ -451,7 +451,8 @@ static bool EnterSuidSandbox(sandbox::SetuidSandboxClient* setuid_sandbox,
   // Note: a non-dumpable process can't be debugged. To debug sandbox-related
   // issues, one can specify --allow-sandbox-debugging to let the process be
   // dumpable.
-  const CommandLine& command_line = *CommandLine::ForCurrentProcess();
+  const base::CommandLine& command_line =
+      *base::CommandLine::ForCurrentProcess();
   if (!command_line.HasSwitch(switches::kAllowSandboxDebugging)) {
     prctl(PR_SET_DUMPABLE, 0, 0, 0, 0);
     if (prctl(PR_GET_DUMPABLE, 0, 0, 0, 0)) {