REGRESSION (WebKit2): Reverse conversion doesn't work in Kotoeri
        https://bugs.webkit.org/show_bug.cgi?id=58066
        <rdar://problem/8965302>

        * Scripts/webkit2/messages.py:
        * Shared/mac/AttributedString.h: Added.
        * Shared/mac/AttributedString.mm: Added.
        (WebKit::AttributedString::encode):
        (WebKit::AttributedString::decode):
        Added an class that wraps NSAttributedString. As far as I can tell, one can't pass a CF
        or NS object to another process without wrapping it in a C++ one.
        
        * Shared/mac/ArgumentCodersMac.h: Added.
        * Shared/mac/ArgumentCodersMac.mm: Added.
        Added coders for Foundation objects, similar to ArgumentCodersCF. There are two reasons why
        these are needed:
        1) Even though most Foundation objects are toll free bridged with CF, CFGetTypeID() doesn't
        work properly for them (I've been just getting 1).
        2) NSColor isn't toll free bridged to CF.
        This adds just the types necessary for editing NSAttributedString (and I don't yet know what
        happens with attachments).

        * UIProcess/API/mac/WKView.mm: (-[WKView attributedSubstringFromRange:]):
        * UIProcess/WebPageProxy.h:
        * UIProcess/mac/WebPageProxyMac.mm:
        (WebKit::WebPageProxy::getAttributedSubstringFromRange):
        * WebKit2.xcodeproj/project.pbxproj:
        * WebProcess/WebPage/WebPage.h:
        * WebProcess/WebPage/WebPage.messages.in:
        Boilerplate code for making a sync call to web process.

        * WebProcess/WebPage/mac/WebPageMac.mm: (WebKit::WebPage::getAttributedSubstringFromRange):
        Ported from WebHTMLView.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@83204 268f45cc-cd09-0410-ab3c-d52691b4dbfc