fnPopupOpened = function () {
                this._proxyFixSize();

                if (!this._sInitialFocusId) {
                    var sInitFocusId = _fnGetInitialFocus(this);

                    // Compare the initial focus id with the current focus that is
                    // stored in the FocusHandler in the core.
                    // If the initial focus was set properly already by the Popup don't focus twice.
                    if (sInitFocusId !== sap.ui.getCore().getCurrentFocusedControlId()) {
                        var oControl = jQuery(document.getElementById(sInitFocusId));
                        oControl.trigger("focus");
                    }
                }

                if (!this._sResizeID) {
                    // register the ResizeHandler for the content of the toolPopup and not the whole toolPopup itself.
                    // In this way when resized the toolPopup does not change its height indefinitely.
                    this._sResizeID = ResizeHandler.register(this.$('content')[0], this._proxyOnResize);
                }

                // forward the Popup's opened event accordingly
                // was added in "1.19.0" as a fix for a CSN and was downported to "1.18.2" and "1.16.6"
                this.fireOpened();
            }
Function is called via 'jQuery.proxy()' when the ToolPopup has been opened
including the fade-in-animation of the Popup

@private