[presubmit] Enable readability/namespace linter checking.

test/cctest/test-microtask-delivery.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 33 matching lines @@
   ~HarmonyIsolate() {
     isolate_->Exit();
     isolate_->Dispose();
   }
 
   v8::Isolate* GetIsolate() const { return isolate_; }
 
  private:
   v8::Isolate* isolate_;
 };
-}
+}  // namespace
 
 
 TEST(MicrotaskDeliverySimple) {
   HarmonyIsolate isolate;
   v8::HandleScope scope(isolate.GetIsolate());
   LocalContext context(isolate.GetIsolate());
   CompileRun(
       "var ordering = [];"
       "var resolver = {};"
       "function handler(resolve) { resolver.resolve = resolve; }"
@@ skipping 62 matching lines @@
         "foo.id++;");
   }
   {
     LocalContext context4(isolate.GetIsolate());
     context4->Global()->Set(
         v8::String::NewFromUtf8(isolate.GetIsolate(), "obj"), obj);
     isolate.GetIsolate()->RunMicrotasks();
     CHECK_EQ(2, CompileRun("obj.calls")->Int32Value());
   }
 }