Correct enum THREE.MOUSE to include the only valid values {LEFT, MIDDLE, RIGHT}. Remove properties THREE.LEFT, THREE.MIDDLE, and THREE.RIGHT as those are not defined in the most recent version of Three.js (r71).

threejs/three.d.ts

@@ -11,10 +11,7 @@ declare module THREE {
     export var REVISION: string;
 
     // https://developer.mozilla.org/en-US/docs/Web/API/MouseEvent.button
-    export enum MOUSE { }
-    export var LEFT: MOUSE;
-    export var MIDDLE: MOUSE;
-    export var RIGHT: MOUSE;
+    export enum MOUSE {LEFT, MIDDLE, RIGHT}
 
     // GL STATE CONSTANTS
     export enum CullFace { }