[Performance] Deactive mct-resize on destroy

Deactive mct-resize when its containing scope is destroyed;
that is, don't go on polling for size changes indefinitely.
Issue discovered/addressed in the context of investigating
sluggishness of plotting in WTD-717.

platform/commonUI/general/src/directives/MCTResize.js

@@ -35,7 +35,8 @@ define(
 
             // Link; start listening for changes to an element's size
             function link(scope, element, attrs) {
-                var lastBounds;
+                var lastBounds,
+                    active = true;
 
                 // Determine how long to wait before the next update
                 function currentInterval() {
@@ -62,8 +63,18 @@ define(
                         width: element[0].offsetWidth,
                         height: element[0].offsetHeight
                     });
+                    if (active) {
                         $timeout(onInterval, currentInterval());
                     }
+                }
+
+                // Stop running in the background
+                function deactivate() {
+                    active = false;
+                }
+
+                // Unregister once out-of-scope
+                scope.$on("$destroy", deactivate);
 
                 // Handle the initial callback
                 onInterval();