oops - didn't mean to remove that bit of doc

src/webrtc/call.js

@@ -25,6 +25,22 @@ const DEBUG = true;  // set true to enable console logging.
 
 // events: hangup, error(err), replaced(call), state(state, oldState)
 
+/**
+ * Fires whenever an error occurs when call.js encounters an issue with setting up the call.
+ * <p>
+ * The error given will have a code equal to either `MatrixCall.ERR_LOCAL_OFFER_FAILED` or
+ * `MatrixCall.ERR_NO_USER_MEDIA`. `ERR_LOCAL_OFFER_FAILED` is emitted when the local client
+ * fails to create an offer. `ERR_NO_USER_MEDIA` is emitted when the user has denied access
+ * to their audio/video hardware.
+ *
+ * @event module:webrtc/call~MatrixCall#"error"
+ * @param {Error} err The error raised by MatrixCall.
+ * @example
+ * matrixCall.on("error", function(err){
+ *   console.error(err.code, err);
+ * });
+ */
+
 /**
  * Construct a new Matrix Call.
  * @constructor