browser-plugin: Send a JSON string for the detail data with the events.

content/test/data/browser_plugin_embedder.html

Index: content/test/data/browser_plugin_embedder.html
diff --git a/content/test/data/browser_plugin_embedder.html b/content/test/data/browser_plugin_embedder.html
index c7294a2236869419f90d7b43e194ae9ebcd6de87..0da05f2fbf2c934cd2eda104f3171f5d9809cf94 100644
--- a/content/test/data/browser_plugin_embedder.html
+++ b/content/test/data/browser_plugin_embedder.html
@@ -1,9 +1,9 @@
 <script type="text/javascript">
 function loadAbort(evt) {
-  document.title = evt.detail.reason;
+  document.title = JSON.parse(evt.detail).reason;
 }
 function loadStart(evt) {
-  document.title = evt.detail.url;
+  document.title = JSON.parse(evt.detail).url;
 }
 function loadStop(evt) {
   document.title = "loadStop";
@@ -11,17 +11,19 @@ function loadStop(evt) {
 
 var commitIsTopLevel;
 function loadCommit(evt) {
-  document.title = "loadCommit:" + evt.detail.url;
-  commitIsTopLevel = evt.detail.isTopLevel;
+  var detail = JSON.parse(evt.detail);
+  document.title = "loadCommit:" + detail.url;
+  commitIsTopLevel = detail.isTopLevel;
 }
 
 var redirectOldUrl;
 var redirectNewUrl;
 function loadRedirect(event) {
   document.title = "redirected";
-  if (event.detail.isTopLevel) {
-    redirectOldUrl = event.detail.oldUrl;
-    redirectNewUrl = event.detail.newUrl;
+  var detail = JSON.parse(event.detail);
+  if (detail.isTopLevel) {
+    redirectOldUrl = detail.oldUrl;
+    redirectNewUrl = detail.newUrl;
   }
 }
 function SetSrc(src) {