[PLAYER-7] fix issue when destroy a not fully initialized player

[jparez]

Description

When calling setupRender and destroy() in a loop destroy() destroy try to delete object not already load

see https://genymobile.atlassian.net/browse/PLAYER-7

Type of change

• Bug fix (non-breaking change which fixes an issue)

[pgivel]

LGTM as is, but a couple suggestions for improvment.

[pgivel]

I think it could be a little bit cleaner to reverse the condition:

Suggested change

	/**
	* if the websocket is in connecting state,
	* we can't destroy the instance cause object is not fully initialized
	*/
	if (this.webRTCWebsocket.readyState !== 0) {
	/**
	* if the websocket is in connecting state,
	* we can't destroy the instance cause object is not fully initialized
	*/
	if (this.webRTCWebsocket.readyState === 0) {
	return;
	}

I don't know if we could also add an event listener for when the socket is ready ? Maybe it's useless since the page would get closed anyway? I was thinking of something like this:

Suggested change

	/**
	* if the websocket is in connecting state,
	* we can't destroy the instance cause object is not fully initialized
	*/
	if (this.webRTCWebsocket.readyState !== 0) {
	/**
	* if the websocket is in connecting state,
	* we can't destroy the instance cause object is not fully initialized
	*/
	if (this.webRTCWebsocket.readyState === 0) {
	this.addListener(this.webRTCWebsocket, 'open', this.destroy.bind(this), {once: true});
	return;
	}