src/vs/workbench/browser/layout.ts/Layout/setSideBarPosition
class Layout:	private setSideBarPosition(position: Position): void {
		const activityBar = this.getPart(Parts.ACTIVITYBAR_PART);
		const sideBar = this.getPart(Parts.SIDEBAR_PART);
		const wasHidden = this.state.sideBar.hidden;
		const newPositionValue = (position === Position.LEFT) ? 'left' : 'right';
		const oldPositionValue = (this.state.sideBar.position === Position.LEFT) ? 'left' : 'right';
		this.state.sideBar.position = position;

		// Adjust CSS
		const activityBarContainer = assertIsDefined(activityBar.getContainer());
		const sideBarContainer = assertIsDefined(sideBar.getContainer());
		activityBarContainer.classList.remove(oldPositionValue);
		sideBarContainer.classList.remove(oldPositionValue);
		activityBarContainer.classList.add(newPositionValue);
		sideBarContainer.classList.add(newPositionValue);

		// Update Styles
		activityBar.updateStyles();
		sideBar.updateStyles();

		// Layout
		if (!wasHidden) {
			this.state.sideBar.width = this.workbenchGrid.getViewSize(this.sideBarPartView).width;
		}

		if (position === Position.LEFT) {
			this.workbenchGrid.moveViewTo(this.activityBarPartView, [2, 0]);
			this.workbenchGrid.moveViewTo(this.sideBarPartView, [2, 1]);
		} else {
			this.workbenchGrid.moveViewTo(this.sideBarPartView, [2, 4]);
			this.workbenchGrid.moveViewTo(this.activityBarPartView, [2, 4]);
		}

		this.layout();
	}