Realize IWYU pattern for handles.h header.

src/messages.h

 // Copyright 2006-2008 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.
 
 // The infrastructure used for (localized) message reporting in V8.
 //
 // Note: there's a big unresolved issue about ownership of the data
 // structures used by this framework.
 
 #ifndef V8_MESSAGES_H_
 #define V8_MESSAGES_H_
 
-// Forward declaration of MessageLocation.
-namespace v8 {
-namespace internal {
-class MessageLocation;
-} }  // namespace v8::internal
-
-
-class V8Message {
- public:
-  V8Message(char* type,
-            v8::internal::Handle<v8::internal::JSArray> args,
-            const v8::internal::MessageLocation* loc) :
-      type_(type), args_(args), loc_(loc) { }
-  char* type() const { return type_; }
-  v8::internal::Handle<v8::internal::JSArray> args() const { return args_; }
-  const v8::internal::MessageLocation* loc() const { return loc_; }
- private:
-  char* type_;
-  v8::internal::Handle<v8::internal::JSArray> const args_;
-  const v8::internal::MessageLocation* loc_;
-};
-
+#include "src/base/smart-pointers.h"
+#include "src/list.h"
 
 namespace v8 {
 namespace internal {
 
-struct Language;
+// Forward declarations.
+class JSMessageObject;
+class LookupIterator;
 class SourceInfo;
 
 class MessageLocation {
  public:
   MessageLocation(Handle<Script> script, int start_pos, int end_pos,
                   Handle<JSFunction> function = Handle<JSFunction>())
       : script_(script),
         start_pos_(start_pos),
         end_pos_(end_pos),
         function_(function) {}
@@ skipping 443 matching lines @@
 
   static MUST_USE_RESULT MaybeHandle<String> GetStringifiedProperty(
       Isolate* isolate, LookupIterator* property_lookup,
       Handle<String> default_value);
 
   List<Handle<JSObject> > visited_;
 };
 } }  // namespace v8::internal
 
 #endif  // V8_MESSAGES_H_