Remove some strict-XML-compatibility issues.
Add wrapper classes for elements returned by *Definition#render():
- HFrameDeclaration represents an empty <hf:frame def="frameID">
- HFramesetResult represents a frameset doc with top-level frame declarations
- HBodyResult represents a <hf:body> with contents including frame declarations

Start simplifying var names inside methods, e.g. hframe -> frame, frameDef -> definition

DOM.getTagName() now incorporates element.scopeName on IE8, IE9.