This worked for me:
- Quit Chrome (ensure you don't have any running).
- Go to the Chrome user profile directory
- Put your new avatar png file into the "Default" subdirectory.
- Open/edit the "Local State" file in a good text editor.
Find the "profile" section; it resembles this:
Ignore the "avatar_icon" line - it's not what you want!
Edit the "Default" profile section and add the following lines (I put them in the right alphabetical order amongst the other lines; I'm not sure whether that matters):
Save the "Local State" file.
- Start Chrome.
If you want to do this for other profiles, just do the above steps for a different directory besides "Default" (for example, "Profile 1").
I had run Chrome with the
--gaia-profile-info switch before I tried the above, so you may need to do that first, but I'm not sure.
You may want to star the Chrome issue 91230 http://code.google.com/p/chromium/issues/detail?id=91230 to get a proper UI for this type of thing again.
(I also answered this at How do I access/edit the Chrome user avatar images? on Super User.)