Closes the Blob object by releasing the stream held by the Blob and the associated file or memory resource.
This method has no parameters.
This method does not return a value.
After calling this method, performing addition operations on the Blob object fails and throws an exception.
Close should be used in order to deterministically release the memory or file backing the blob. If close is called on the blob while there is a currently pending operation such as an XHR send request, a FileReader read on the blob, or a web socket operation to send the blob, then that operation will be cancelled. The blob should not be closed until these pending read operations are finished.