Tests sendMessage with invalid message.
{"method":"Inspector.workerScriptLoaded","params":{}}
JSON syntax error..
{"error":{"code":-32700,"message":"JSON: string literal expected at position 57"}}
JSON with primitive value..
{"error":{"code":-32600,"message":"Message must be an object"}}
JSON without method property..
{"error":{"code":-32600,"message":"Message must have integer 'id' property"}}
JSON without id property..
{"error":{"code":-32600,"message":"Message must have integer 'id' property"}}
Valid JSON..
{"id":1,"result":{"result":{"type":"number","value":42,"description":"42"}}}