Called by send, or once flash is loaded, to actually send the bytes.
@private
function() {
        var me = this, req, status;
        me.javascriptId = Ext.data.flash.BinaryXhr.registerConnection(me);
        
        // Create the request object we're sending to flash
        req = {
            method: me.method, // ignored since we always POST binary data
            url: me.url,
            user: me.user,
            password: me.password,
            mimeType: me.mimeType,
            requestHeaders: me.requestHeaders,
            body: me.body,
            javascriptId: me.javascriptId
        };
        status = Ext.data.flash.BinaryXhr.flashPlugin.postBinary(req);
    }