spelling: compatibility

examples/assets/library/iframe-content.js

@@ -681,7 +681,7 @@
 
     function isInitMsg(){
       //test if this message is from a child below us. This is an ugly test, however, updating
-      //the message format would break backwards compatibity.
+      //the message format would break backwards compatibility.
       return event.data.split(':')[2] in {'true':1,'false':1};
     }
 

examples/assets/library/iframe.js

@@ -213,7 +213,7 @@
 
     function isMessageFromMetaParent(){
       //test if this message is from a parent above us. This is an ugly test, however, updating
-      //the message format would break backwards compatibity.
+      //the message format would break backwards compatibility.
       var retCode = messageData.type in {'true':1,'false':1,'undefined':1};
 
       if (retCode){