Objj2 compiler fixes

Compiled all files individually:

- Added missing imports.
- Added @class/@global declarations to break circular dependencies.
- Misc. code cleanup.

Conflicts:
	AppKit/CPWindow/_CPWindow.j
	AppKit/Platform/DOM/CPPlatformWindow+DOM.j

AppKit/CPRuleEditor/_CPPredicateEditorRowNode.j

@@ -1,9 +1,25 @@
 /*
- *     Created by cacaodev@gmail.com.
- *     Copyright (c) 2011 Pear, Inc. All rights reserved.
+ * Created by cacaodev@gmail.com.
+ * Copyright (c) 2011 Pear, Inc. All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-//@class _CPPredicateEditorTree;
+@import <Foundation/CPObject.j>
+@import <Foundation/CPString.j>
+
 @implementation _CPPredicateEditorRowNode : CPObject
 {
     _CPPredicateEditorTree                   tree @accessors;