src/vs/workbench/browser/layout.ts/Layout/centerEditorLayout
class Layout:	centerEditorLayout(active: boolean, skipLayout?: boolean): void {
		this.state.editor.centered = active;

		this.storageService.store(Storage.CENTERED_LAYOUT_ENABLED, active, StorageScope.WORKSPACE, StorageTarget.USER);

		let smartActive = active;
		const activeEditor = this.editorService.activeEditor;

		const isSideBySideLayout = activeEditor
			&& activeEditor instanceof SideBySideEditorInput
			// DiffEditorInput inherits from SideBySideEditorInput but can still be functionally an inline editor.
			&& (!(activeEditor instanceof DiffEditorInput) || this.configurationService.getValue('diffEditor.renderSideBySide'));

		const isCenteredLayoutAutoResizing = this.configurationService.getValue('workbench.editor.centeredLayoutAutoResize');
		if (
			isCenteredLayoutAutoResizing
			&& (this.editorGroupService.groups.length > 1 || isSideBySideLayout)
		) {
			smartActive = false;
		}

		// Enter Centered Editor Layout
		if (this.editorGroupService.isLayoutCentered() !== smartActive) {
			this.editorGroupService.centerLayout(smartActive);

			if (!skipLayout) {
				this.layout();
			}
		}

		this._onDidChangeCenteredLayout.fire(this.state.editor.centered);
	}