Show error when workspace ceases to exist

plugins/c9.ide.dialog.common/alert_internal.js

@@ -42,6 +42,8 @@ define(function(require, module, exports) {
                     .replace(/\n/g, "<br />")
                     .replace(/(https?:\/\/[^\s]*\b)/g, "<a href='$1' target='_blank'>$1</a>");
                 
+                plugin.getElement("ok").setCaption(options.yes || "OK");
+                
                 plugin.update([
                     { id: "dontshow", visible: options && options.showDontShow }
                 ]);

plugins/c9.vfs.client/endpoint.js

@@ -225,6 +225,10 @@ define(function(require, exports, module) {
                             callback(fatalError(res.error.message, "dashboard"));
                             return;
                         }
+                        else if (err.code == 404) {
+                            callback(fatalError("This workspace no longer appears to exist or failed to be created.", "dashboard"));
+                            return;
+                        }
                         else if (err.code === 428 && res.error) {
                             emit("restore", {
                                 projectState: res.error.projectState,

plugins/c9.vfs.client/vfs_client.js

@@ -253,7 +253,7 @@ define(function(require, exports, module) {
                         err.message = "SSH permission denied. Please review your workspace configuration.";
                     return showAlert("Workspace Error", "Unable to access your workspace", err.message, function() {
                         window.location = dashboardUrl;
-                    });
+                    }, { yes: "Return to dashboard" });
                 case "reload":
                     lastError = showError(err.message + ". Please reload this window.", -1);
                     setTimeout(function() {