[MD Bookmarks] Persist collapsed folders between page loads.

chrome/browser/resources/md_bookmarks/folder_node.js

Index: chrome/browser/resources/md_bookmarks/folder_node.js
diff --git a/chrome/browser/resources/md_bookmarks/folder_node.js b/chrome/browser/resources/md_bookmarks/folder_node.js
index 40fb4a9db70188c90ac1882cdc4869b27e23b477..1b7792fa6091f12343fcc5cd9d6b5df352122e9e 100644
--- a/chrome/browser/resources/md_bookmarks/folder_node.js
+++ b/chrome/browser/resources/md_bookmarks/folder_node.js
@@ -79,6 +79,8 @@ Polymer({
   toggleFolder_: function(e) {
     this.dispatch(
         bookmarks.actions.changeFolderOpen(this.item_.id, this.isClosed_));
+    window.localStorage[LOCAL_STORAGE_CLOSED_FOLDERS_KEY] =

[tsergeant, 2017/03/29 04:43:24]

I'm a bit torn about where this should live. On one hand, maybe it should live
in app.js, alongside the code which loads the state from localstorage. On the
other hand, it does kind of make sense to have it here where it changes.

Did you think about putting it in app? Any particular reason why you went for
here?

[calamity, 2017/03/30 03:16:04]

Yeah, basically because this is where it changes. I think you're right actually.
This won't pick up more subtle things like openAncestorFolders etc.

+        JSON.stringify(this.getState().closedFolders);
     e.stopPropagation();
   },