LT-259 Adding warning for when user attempts to close the Lesion Tracker before saving measurements [INTEGRATING NEW MODULE INTO VIEWER + DOCUMENTATION]

Packages/ohif-viewerbase/client/lib/unloadHandlers.js

@@ -0,0 +1,12 @@
+import { OHIF } from 'meteor/ohif:core';
+
+export const unloadHandlers = {
+    beforeUnload: function(event) {
+        // Check for any unsaved changes on viewer namespace...
+        if (OHIF.ui.unsavedChanges.probe('viewer.*') > 0) {
+            let confirmationMessage = 'You have unsaved changes!';
+            event.returnValue = confirmationMessage;
+            return confirmationMessage;
+        }
+    }
+};