rref #5392. Show close button when chat app screen is empty

app/app.css

@@ -2289,7 +2289,7 @@ table.dataTable thead .sorting:after {
     margin-top: 15px;
 }
 
-.chat-app .conversation-header .close-chat-app {
+.chat-app .conversation-header .close-chat-app, .chat-app .conversation-section-empty .close-chat-app  {
 	display: inline-block;
     float: left;
     width: 40px;
@@ -2303,6 +2303,13 @@ table.dataTable thead .sorting:after {
     cursor: pointer;
 }
 
+.chat-app .conversation-section-empty .close-chat-app {
+    display: block;
+    position: absolute;
+    right: 15px;
+    top: 0px;
+}
+
 .chat-app .conversation-header .chat-app-actions {
 	display: inline-block;
     float: left;
@@ -2374,7 +2381,7 @@ table.dataTable thead .sorting:after {
 	border-radius:100%;
 }
 
-.chat-app .conversation-section .conversation-body .beginning-of-conversation {
+.chat-app .conversation-section .conversation-body .beginning-of-conversation, .chat-app .conversation-section-empty .conversation-body {
 	text-align: center;
     font-family: 'robotobold';
     font-size: 20px;
@@ -2384,6 +2391,10 @@ table.dataTable thead .sorting:after {
     border-bottom: 1px solid #f3f3f3;
 }
 
+.chat-app .conversation-section-empty .conversation-body {
+    padding-top: 100px;
+}
+
 .chat-app .conversation-section .conversation-body .conversation-block {
 	display:block;
 	position:relative;

app/components/messaging/templates/conversation.html

 <span class="loader" ng-show="loadingChannel"></span>
-<div class="conversation-section" ng-hide="selectedChannel">
-    <div class="conversation-body" >
-        <div class="conversation-body-inner">
 
-            <div class="beginning-of-conversation">
-                Select or create channel to begin conversation
-            </div>
-        </div>
+<div class="conversation-section conversation-section-empty" ng-hide="selectedChannel">
+    <div class="close-chat-app" ng-click="hideApp()">
+        <span class="glyphicon glyphicon-remove" ></span>
+    </div>
+    <div class="conversation-body" >
+        Select or create channel to begin conversation
     </div>
 </div>
+
 <div class="conversation-section" ng-hide="loadingChannel || !selectedChannel">
     <div class="conversation-header">
         <div class="conversation-user">