Don't use ENABLE() macro in an exported header.

* platform/ios/wak/WAKResponder.h:

Source/WebKit/ios: Clean up exports and headers for iOS.

* Misc/WebNSStringDrawing.h: Don't use PLATFORM() macro in an exported header.
* WebCoreSupport/WebFrameIOS.h: Ditto.
* WebCoreSupport/WebSelectionRect.h: Ditto.

Source/WebKit/mac: Clean up exports and headers for iOS.

Need to export WebArchivePboardType on Mac and iOS.

* WebKit.exp:
* WebKit.mac.exp:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@162024 268f45cc-cd09-0410-ab3c-d52691b4dbfc