added extra webcam warning for Chrome users

bigbluebutton-client/src/org/bigbluebutton/main/views/CameraDisplaySettings.mxml

@@ -259,6 +259,7 @@ with BigBlueButton; if not, see <http://www.gnu.org/licenses/>.
 				//        controls.btnStartPublish.enabled = true;
 				_waitingForActivation = false;
 				btnStartPublish.enabled = true;
+				_videoHolder.imgChromeHelp.visible = false;
 			}
 		}
 		
@@ -293,6 +294,12 @@ with BigBlueButton; if not, see <http://www.gnu.org/licenses/>.
 		
 		private function activationTimeout(e:TimerEvent):void {
 			_videoHolder.showWarning('bbb.video.publish.hint.cameraIsBeingUsed');
+			
+			//check for Chrome and show image
+			var browserType:Array = ExternalInterface.call('determineBrowser');
+			if (browserType[0] == "Chrome") {
+				_videoHolder.imgChromeHelp.visible = true;
+			}
 		} 
 		
 		private function showCameraSettings():void {

bigbluebutton-client/src/org/bigbluebutton/main/views/VideoHolder.mxml

@@ -71,7 +71,8 @@ with BigBlueButton; if not, see <http://www.gnu.org/licenses/>.
   <mx:Fade id="dissolveIn" duration="1000" alphaFrom="0.0" alphaTo="1.0"/>
   
   <mx:UIComponent id="_videoHolder"/>
-  
+  <mx:Image id="imgChromeHelp" y="60" x="{this.width/2 - imgChromeHelp.width/2}" visible="false"
+			source="@Embed('assets/chrome-allow-mic-access.png')"/>
   <mx:Text id="lblWarning" width="100%" textAlign="center" fontSize="14" fontWeight="bold" 
            y="{this.height - lblWarning.height - 30}" 
            visible="true" selectable="false" hideEffect="{dissolveOut}" showEffect="{dissolveIn}"/>