src/vs/workbench/contrib/webview/browser/baseWebviewElement.ts/BaseWebview/_send
class BaseWebview:	protected _send(channel: string, data?: any): void {
		if (this._state.type === WebviewState.Type.Initializing) {
			this._state.pendingMessages.push({ channel, data });
		} else {
			this.doPostMessage(channel, data);
		}
	}