Converted remoting.Error from an enum to a class

remoting/webapp/crd/js/it2me_helpee_channel.js

Index: remoting/webapp/crd/js/it2me_helpee_channel.js
diff --git a/remoting/webapp/crd/js/it2me_helpee_channel.js b/remoting/webapp/crd/js/it2me_helpee_channel.js
index 79c016b3dd7fc3375f27428e2213b78e3b1c0293..71a849e22de562bfe4c5f53fb2d7a1944633d916 100644
--- a/remoting/webapp/crd/js/it2me_helpee_channel.js
+++ b/remoting/webapp/crd/js/it2me_helpee_channel.js
@@ -188,8 +188,8 @@ remoting.It2MeHelpeeChannel.prototype.onHangoutMessage_ = function(message) {
         return true;
     }
     throw new Error('Unsupported message method=' + message.method);
-  } catch(/** @type {Error} */ error) {
-    this.sendErrorResponse_(message, error.message);
+  } catch(/** @type {!Error} */ error) {
+    this.sendErrorResponse_(message, error);
   }
   return false;
 };
@@ -227,9 +227,8 @@ remoting.It2MeHelpeeChannel.prototype.handleIsHostInstalled_ =
 remoting.It2MeHelpeeChannel.prototype.handleDownloadHost_ = function(message) {
   try {
     this.hostInstaller_.download();
-  } catch (/** @type {*} */ e) {
-    var error = /** @type {Error} */ (e);
-    this.sendErrorResponse_(message, error.message);
+  } catch (/** @type {!Error} */ error) {
+    this.sendErrorResponse_(message, error);
   }
 };
 
@@ -264,9 +263,8 @@ remoting.It2MeHelpeeChannel.prototype.handleConnect_ =
       /** @param {{email:string, token:string}|Promise} result */
       .then(function(result) {
         that.connectToHost_(result.email, result.token);
-      /** @param {*} reason */
-      }).catch(function(reason) {
-        that.sendErrorResponse_(message, /** @type {Error} */ (reason));
+      }).catch(function(/** !Error */ reason) {
+        that.sendErrorResponse_(message, reason);
         that.dispose();
       });
 };
@@ -308,7 +306,7 @@ remoting.It2MeHelpeeChannel.prototype.showConfirmDialogV1_ = function() {
   if(window.confirm(message)) {
     return Promise.resolve();
   } else {
-    return Promise.reject(new Error(remoting.Error.CANCELLED));
+    return Promise.reject(remoting.Error.CANCELLED);
   }
 };
 
@@ -362,14 +360,16 @@ remoting.It2MeHelpeeChannel.prototype.fetchOAuthToken_ = function() {
     return remoting.identity.getToken();
   } else {
       var onError = function(/** * */ error) {
-        if (error === remoting.Error.NOT_AUTHENTICATED) {
+        if (error instanceof remoting.Error &&
+            /** @type {!remoting.Error} */ (error).tag ===
+            remoting.Error.Tag.NOT_AUTHENTICATED) {
           return new Promise(function(resolve, reject) {
             remoting.oauth2.doAuthRedirect(function() {
               remoting.identity.getToken().then(resolve);
             });
           });
         }
-        throw Error(remoting.Error.NOT_AUTHENTICATED);
+        throw remoting.Error.NOT_AUTHENTICATED;
       };
     return /** @type {!Promise<string>} */ (
         remoting.identity.getToken().catch(onError));
@@ -413,7 +413,7 @@ remoting.It2MeHelpeeChannel.prototype.connectToHost_ =
 };
 
 /**
- * @param {remoting.Error} error
+ * @param {!remoting.Error} error
  * @private
  */
 remoting.It2MeHelpeeChannel.prototype.onHostConnectError_ = function(error) {
@@ -457,21 +457,26 @@ remoting.It2MeHelpeeChannel.prototype.onHostStateChanged_ = function(state) {
 
 /**
  * @param {?{method:string, data:Object<string,*>}} incomingMessage
- * @param {string|Error} error
+ * @param {!remoting.Error|!Error} error
  * @private
  */
 remoting.It2MeHelpeeChannel.prototype.sendErrorResponse_ =
     function(incomingMessage, error) {
+  /** @type {string} */
+  var errorMessage;
+
   if (error instanceof Error) {
-    error = error.message;
+    errorMessage = error.message;
+  } else {
+    errorMessage = error.tag;
   }
 
   console.error('Error responding to message method:' +
                 (incomingMessage ? incomingMessage.method : 'null') +
-                ' error:' + error);
+                ' error:' + errorMessage);
   this.hangoutPort_.postMessage({
     method: remoting.It2MeHelpeeChannel.HangoutMessageTypes.ERROR,
-    message: error,
+    message: errorMessage,
     request: incomingMessage
   });
 };