Sync diagnostics (Needs update)

"Classic" about:sync page
Updates on the fly
- Try moving a bookmark, or stopping and starting sync
Some stuff will eventually be moved out, but page is still useful as an overview

Dump to text button
- Dumps all info from about and events tab
  - But can also select datatypes info to dump
- Can be used to tell users to:
  - Open about:sync
  - Repro the problem if possible
  - Wait a while (15-30 seconds)
  - Go to data tab
  - Dump info, paste into bug (or email privately if there's sensitive info)
- Event log will probably be most useful part
- Redacts sensitive info
Room for improvement
- Automatically highlight dumped text, add "Copy to clipboard" button
- Button to add to an existing bug, or create a new one

If a notification is received when the page (not just the tab) is open, a counter will increment (one for each data type)
- Try moving a bookmark, setting a preference, or stopping and starting sync
- Takes ~5-10 seconds for a notification to bounce back
- Total Count of invalidations per each data type
- Session Counters reset if you reload
Room for improvement
- More detailed connection stats
  - How long has connection been up? Which XMPP server/port? How long ago was the last message sent/received?

Shows all sync events (i.e., functions in SyncManager::Observer and incoming notifications) that happen as long as the page is open
- Try moving a bookmark, or starting sync (dumps lots of data!)
- Doesn't quite log everything yet
- Only logs events after backend is initialized
- Resets if you reload
Room for improvement
- Store last N events (C++ side) so you can open it right when you hit a problem and still get some useful info
- Also log requests/responses to HTTP server
- Perhaps more logging for sync setup events
- Better display (82866)
- Start logging even before backend is initialized (tricky)

Shows sync nodes
- Sync nodes are structured in a tree.
- Each data type has a top-level node which is a child of the root node
- Only bookmarks sub-tree has true tree structure
  - Everything else is just a list under the top-level node
- Use links to navigate tree: parent, first child, predecessor, successor
- Ignore specifics information for folder
Tree view version
- Tree visualized on the left, details of selected node on the right
Does not auto-update; you need to refresh
- Be careful, you may lose logged events; you can always open a new about:sync tab instead
Room for improvement
- Implement auto-updating (hard)
- Add a refresh button (easier)

Searches expressions in all the nodes
Supports Regex over the JSONified version of each node
Has quick searches to provide for easy access to interesting nodes. So far:
- Unapplied updates
- Unsynced items
- Delted items
- Conflicted items (unapplied and unsynced)

Sync talks to the sync server via POSTing to clients4.google.com.
Sync talks to the notification servers via XMPP (talk.google.com).
Both sockets should show up in chrome://net-internals (after 82365 is fixed).

Data type-specific tabs
- Model associators / change processors have access to the SyncService, so shouldn't be too hard to emit events or reply to calls
- Probably easier for things that live on the UI thread
Some way to capture VLOG() events
Should be obvious when sync isn't working
Use HTML notifications for events
Front-end for memory usage info (Lingesh is working on backend)