<webview>: Partially migrate loadcommit event from content to chrome

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 9501d19df3e7586f5d13c6558bc771110a87739e..914c12a67769603b35389228ff972c081e003d12 100644
--- a/content/test/data/browser_plugin_embedder.html
+++ b/content/test/data/browser_plugin_embedder.html
@@ -14,13 +14,6 @@ function loadStop(evt) {
   document.title = "loadStop";
 }
 
-var commitIsTopLevel;
-function loadCommit(evt) {
-  var detail = JSON.parse(evt.detail);
-  document.title = "loadCommit:" + detail.url;
-  commitIsTopLevel = detail.isTopLevel;
-}
-
 var redirectOldUrl;
 var redirectNewUrl;
 function loadRedirect(event) {
@@ -107,6 +100,5 @@ function receiveMessage(event) {
   plugin.addEventListener('-internal-loadredirect', loadRedirect);
   window.addEventListener('message', receiveMessage, false);
   plugin.addEventListener('-internal-loadstop', loadStop);
-  plugin.addEventListener('-internal-loadcommit', loadCommit);
   plugin.addEventListener('-internal-sizechanged', sizeChanged);
 </script>