Updated screen sharing styling and icon

app/lib/components/Room.jsx

@@ -31,15 +31,28 @@ class Room extends React.Component
 		} = this.props;
 
 		let screenState;
+		let screenTip;
 
 		if (me.needExtension)
+		{
 			screenState = 'need-extension';
+			screenTip = 'Install screen sharing extension';
+		}
 		else if (!me.canShareScreen)
+		{
 			screenState = 'unsupported';
+			screenTip = 'Screen sharing not supported';
+		}
 		else if (screenProducer)
+		{
 			screenState = 'on';
+			screenTip = 'Stop screen sharing';
+		}
 		else
+		{
 			screenState = 'off';
+			screenTip = 'Start screen sharing';
+		}
 
 		return (
 			<Appear duration={300}>
@@ -96,7 +109,7 @@ class Room extends React.Component
 					<div className='sidebar'>
 						<div
 							className={classnames('button', 'screen', screenState)}
-							data-tip='Toggle screen sharing'
+							data-tip={screenTip}
 							data-type='dark'
 							onClick={() =>
 							{

app/resources/images/share-screen-white.svg

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px" viewBox="0 0 96 96" style="enable-background:new 0 0 96 96;" xml:space="preserve">
+<style type="text/css">
+	.st0{fill:#FFFFFF;}
+</style>
+<g id="XMLID_2_">
+	<path id="XMLID_6_" class="st0" d="M66.3,61.8c2.5,0,4.6-2.1,4.6-4.6l0-22.9c0-2.5-2.1-4.6-4.6-4.6H29.7c-2.5,0-4.6,2-4.6,4.6v22.9
+		c0,2.5,2,4.6,4.6,4.6h-9.2v4.6h55v-4.6H66.3z M50.3,53.7v-5c-6.4,0-10.6,1.9-13.8,6.2c1.3-6.1,4.8-12.2,13.8-13.5v-4.9l9.2,8.5
+		L50.3,53.7z"/>
+</g>
+</svg>

app/stylus/components/Room.styl

@@ -238,7 +238,7 @@
 				}
 
 				&.off {
-					background-image: url('/resources/images/share-screen-black.svg');
+					background-image: url('/resources/images/share-screen-white.svg');
 				}
 
 				&.unsupported {