Added event.preventDefault() to the other controls as per discussion in #1986.

src/extras/controls/FirstPersonControls.js

@@ -124,7 +124,9 @@ THREE.FirstPersonControls = function ( object, domElement ) {
 
 	this.onKeyDown = function ( event ) {
 
-		switch( event.keyCode ) {
+		event.preventDefault();
+
+		switch ( event.keyCode ) {
 
 			case 38: /*up*/
 			case 87: /*W*/ this.moveForward = true; break;

src/extras/controls/FlyControls.js

@@ -49,7 +49,9 @@ THREE.FlyControls = function ( object, domElement ) {
 
 		}
 
-		switch( event.keyCode ) {
+		event.preventDefault();
+
+		switch ( event.keyCode ) {
 
 			case 16: /* shift */ this.movementSpeedMultiplier = .1; break;
 

src/extras/controls/RollControls.js

@@ -164,7 +164,9 @@ THREE.RollControls = function ( object, domElement ) {
 
 	function onKeyDown( event ) {
 
-		switch( event.keyCode ) {
+		event.preventDefault();
+
+		switch ( event.keyCode ) {
 
 			case 38: /*up*/
 			case 87: /*W*/ forwardSpeed = 1; break;