Stop the UIWebView loading and clear both its and the UITextView's delegates in dealloc.
Stop the UIWebView loading and clear both its and the UITextView's delegates
in dealloc.

This prevents a crash if we have a callback in flight just as we dealloc.

tipbit/ZSSRichTextEditor,tipbit/ZSSRichTextEditor,tipbit/ZSSRichTextEditor,tipbit/ZSSRichTextEditor