src/vs/workbench/contrib/search/browser/searchWidget.ts/SearchWidget/onPreserveCaseKeyDown
class SearchWidget:	private onPreserveCaseKeyDown(keyboardEvent: IKeyboardEvent) {
		if (keyboardEvent.equals(KeyCode.Tab)) {
			if (this.isReplaceActive()) {
				this.focusReplaceAllAction();
			} else {
				this._onBlur.fire();
			}
			keyboardEvent.preventDefault();
		}
		else if (keyboardEvent.equals(KeyMod.Shift | KeyCode.Tab)) {
			this.focusRegexAction();
			keyboardEvent.preventDefault();
		}
	}