Merge from vscode 31e03b8ffbb218a87e3941f2b63a249f061fe0e4 (#4986)

src/vs/editor/contrib/referenceSearch/referencesWidget.ts

@@ -157,9 +157,25 @@ class DecorationsManager implements IDisposable {
 	}
 }
 
-export interface LayoutData {
+export class LayoutData {
 	ratio: number;
 	heightInLines: number;
+
+	static fromJSON(raw: string): LayoutData {
+		let ratio: number | undefined;
+		let heightInLines: number | undefined;
+		try {
+			const data = <LayoutData>JSON.parse(raw);
+			ratio = data.ratio;
+			heightInLines = data.heightInLines;
+		} catch {
+			//
+		}
+		return {
+			ratio: ratio || 0.7,
+			heightInLines: heightInLines || 18
+		};
+	}
 }
 
 export interface SelectionEvent {