fix grid resizing interation with editor (#2427)

src/sql/base/common/event.ts

@@ -0,0 +1,39 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the Source EULA. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+'use strict';
+
+import { Emitter, Event } from 'vs/base/common/event';
+
+/**
+ * Implementation of vs/base/common/event/echo that is clearable
+ * Similar to `buffer` but it buffers indefinitely and repeats
+ * the buffered events to every new listener.
+ */
+export function echo<T>(event: Event<T>, nextTick = false, buffer: T[] = []): { clear: () => void; event: Event<T> } {
+	buffer = buffer.slice();
+
+	event(e => {
+		buffer.push(e);
+		emitter.fire(e);
+	});
+
+	const flush = (listener: (e: T) => any, thisArgs?: any) => buffer.forEach(e => listener.call(thisArgs, e));
+	const clear = () => buffer = [];
+
+	const emitter = new Emitter<T>({
+		onListenerDidAdd(emitter, listener: (e: T) => any, thisArgs?: any) {
+			if (nextTick) {
+				setTimeout(() => flush(listener, thisArgs));
+			} else {
+				flush(listener, thisArgs);
+			}
+		}
+	});
+
+	return {
+		event: emitter.event,
+		clear
+	};
+}