Remove unused import

src/vs/workbench/parts/webview/electron-browser/webviewEditor.ts

@@ -8,7 +8,6 @@ import { domEvent } from 'vs/base/browser/event';
 import { Emitter, Event } from 'vs/base/common/event';
 import { IDisposable } from 'vs/base/common/lifecycle';
 import URI from 'vs/base/common/uri';
-import { TPromise } from 'vs/base/common/winjs.base';
 import { IContextKeyService } from 'vs/platform/contextkey/common/contextkey';
 import { IInstantiationService } from 'vs/platform/instantiation/common/instantiation';
 import { ITelemetryService } from 'vs/platform/telemetry/common/telemetry';