stuff from here into the .m file so this header can be included
	by clients. Also added floatWidthForCharacters:length:.
	* WebCoreSupport.subproj/IFTextRenderer.m:
	(freeWidthMap): Check for NULL.
	(freeGlyphMap): Check for NULL.
	(-[IFTextRenderer slowFloatWidthForCharacters:length:]): Renamed,
	and made it return the float.
	(-[IFTextRenderer floatWidthForCharacters:length:]): Renamed, and
	made it return the float.
	(-[IFTextRenderer widthForCharacters:length:]): Do rounding here.

	* WebCoreSupport.subproj/IFTextRendererFactory.h:
	* WebCoreSupport.subproj/IFTextRendererFactory.m:
	Make the interface slightly easier to use by using the specific types.

	* WebKit.pbproj/project.pbxproj: Exported the headers.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@1132 268f45cc-cd09-0410-ab3c-d52691b4dbfc