Protect AnimationClip against the closure circular reference bug

src/animation/AnimationClip.js

@@ -32,55 +32,6 @@ function AnimationClip( name, duration, tracks ) {
 
 }
 
-AnimationClip.prototype = {
-
-	constructor: AnimationClip,
-
-	resetDuration: function() {
-
-		var tracks = this.tracks,
-			duration = 0;
-
-		for ( var i = 0, n = tracks.length; i !== n; ++ i ) {
-
-			var track = this.tracks[ i ];
-
-			duration = Math.max( duration, track.times[ track.times.length - 1 ] );
-
-		}
-
-		this.duration = duration;
-
-	},
-
-	trim: function() {
-
-		for ( var i = 0; i < this.tracks.length; i ++ ) {
-
-			this.tracks[ i ].trim( 0, this.duration );
-
-		}
-
-		return this;
-
-	},
-
-	optimize: function() {
-
-		for ( var i = 0; i < this.tracks.length; i ++ ) {
-
-			this.tracks[ i ].optimize();
-
-		}
-
-		return this;
-
-	}
-
-};
-
-// Static methods:
-
 Object.assign( AnimationClip, {
 
 	parse: function( json ) {
@@ -98,8 +49,7 @@ Object.assign( AnimationClip, {
 		return new AnimationClip( json.name, json.duration, tracks );
 
 	},
-
-
+	
 	toJSON: function( clip ) {
 
 		var tracks = [],
@@ -122,8 +72,7 @@ Object.assign( AnimationClip, {
 		return json;
 
 	},
-
-
+	
 	CreateFromMorphTargetSequence: function( name, morphTargetSequence, fps, noLoop ) {
 
 		var numMorphTargets = morphTargetSequence.length;
@@ -359,5 +308,52 @@ Object.assign( AnimationClip, {
 
 } );
 
+Object.assign( AnimationClip.prototype, {
+
+	constructor: AnimationClip,
+
+	resetDuration: function() {
+
+		var tracks = this.tracks,
+			duration = 0;
+
+		for ( var i = 0, n = tracks.length; i !== n; ++ i ) {
+
+			var track = this.tracks[ i ];
+
+			duration = Math.max( duration, track.times[ track.times.length - 1 ] );
+
+		}
+
+		this.duration = duration;
+
+	},
+
+	trim: function() {
+
+		for ( var i = 0; i < this.tracks.length; i ++ ) {
+
+			this.tracks[ i ].trim( 0, this.duration );
+
+		}
+
+		return this;
+
+	},
+
+	optimize: function() {
+
+		for ( var i = 0; i < this.tracks.length; i ++ ) {
+
+			this.tracks[ i ].optimize();
+
+		}
+
+		return this;
+
+	}
+
+} );
+
 
 export { AnimationClip };