Empty log file string crashes the server

[deathaxe]

Passing an empty log file string ("xml.logs.file": "") via initalizationOptions crashes the language server.

The expected behavior is an empty string to be handled the same way as null, which just doesn't create a log file.

Traceback:

java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
		at org.eclipse.lsp4j.jsonrpc.services.GenericEndpoint.lambda$null$0(GenericEndpoint.java:67)
		at org.eclipse.lsp4j.jsonrpc.services.GenericEndpoint.request(GenericEndpoint.java:120)
		at org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.handleRequest(RemoteEndpoint.java:261)
		at org.eclipse.lsp4j.jsonrpc.RemoteEndpoint.consume(RemoteEndpoint.java:190)
		at org.eclipse.lemminx.commons.ParentProcessWatcher.lambda$apply$0(ParentProcessWatcher.java:143)
		at org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer.handleMessage(StreamMessageProducer.java:194)
		at org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer.listen(StreamMessageProducer.java:94)
		at org.eclipse.lsp4j.jsonrpc.json.ConcurrentMessageProcessor.run(ConcurrentMessageProcessor.java:113)
		at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
		at java.util.concurrent.FutureTask.run(Unknown Source)
		at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
		at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
		at java.lang.Thread.run(Unknown Source)
	Caused by: java.lang.reflect.InvocationTargetException
		at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
		at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
		at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
		at java.lang.reflect.Method.invoke(Unknown Source)
		at org.eclipse.lsp4j.jsonrpc.services.GenericEndpoint.lambda$null$0(GenericEndpoint.java:65)
		... 12 more
	Caused by: java.lang.IllegalArgumentException: Incorrect file path provided
		at org.eclipse.lemminx.logs.LogHelper.getFileHandler(LogHelper.java:114)
		at org.eclipse.lemminx.logs.LogHelper.initializeRootLogger(LogHelper.java:59)
		at org.eclipse.lemminx.XMLLanguageServer.updateSettings(XMLLanguageServer.java:150)
		at org.eclipse.lemminx.XMLLanguageServer.initialize(XMLLanguageServer.java:111)
		... 17 more

• LemMinX 0.13.1