Include only stuff you need, part 6: Fix cctest.h.

test/cctest/test-object.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "src/factory.h"
+#include "src/handles-inl.h"
+#include "src/handles.h"
+#include "src/isolate.h"
+#include "src/objects.h"
 #include "src/v8.h"
-
 #include "test/cctest/cctest.h"
 
 using namespace v8::internal;
 
 static void CheckObject(Isolate* isolate, Handle<Object> obj,
                         const char* string) {
   Object* print_string = *Object::NoSideEffectsToString(isolate, obj);
   CHECK(String::cast(print_string)->IsUtf8EqualTo(CStrVector(string)));
 }
 
@@ skipping 45 matching lines @@
   CheckObject(isolate, factory->NewError(isolate->error_function(),
                                          factory->empty_string()),
               "Error");
   CheckObject(isolate, factory->NewError(
                            isolate->error_function(),
                            factory->NewStringFromAsciiChecked("fisk hest")),
               "Error: fisk hest");
   CheckObject(isolate, factory->NewJSObject(isolate->object_function()),
               "#<Object>");
 }