GUAC-958: Simplify resize handling (use directive). Only install resize handler after object loads.

guacamole/src/main/webapp/app/client/styles/display.css

@@ -38,18 +38,6 @@ div.main {
     font-size: 0px;
 }
 
-.resize-sensor {
-    height: 100%;
-    width: 100%;
-    position: absolute;
-    left: 0;
-    top: 0;
-    overflow: hidden;
-    border: none;
-    opacity: 0;
-    z-index: -1;
-}
-
 div.displayOuter {
     height: 100%;
     width: 100%;