also warn when quitting mid-call

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

src/components/structures/RoomStatusBar.js

@@ -100,6 +100,10 @@ module.exports = React.createClass({
         this._checkSize();
     },
 
+    componentDidMount: function() {
+        window.addEventListener('beforeunload', this.onPageUnload);
+    },
+
     componentDidUpdate: function() {
         this._checkSize();
     },
@@ -111,6 +115,7 @@ module.exports = React.createClass({
             client.removeListener("sync", this.onSyncStateChange);
             client.removeListener("RoomMember.typing", this.onRoomMemberTyping);
         }
+        window.removeEventListener('beforeunload', this.onPageUnload);
     },
 
     onSyncStateChange: function(state, prevState) {
@@ -128,6 +133,13 @@ module.exports = React.createClass({
         });
     },
 
+    onPageUnload(event) {
+        if (this.props.hasActiveCall) {
+            return event.returnValue =
+                'You seem to be in a call, are you sure you want to quit?';
+        }
+    },
+
     // Check whether current size is greater than 0, if yes call props.onVisible
     _checkSize: function () {
         if (this.props.onVisible && this._getSize()) {