Can't change Google Chrome icon

For every other application package I've looked at, there's a Paste option available in Edit menu after selecting the icon in "Get Info" dialog. For Google Chrome, there isn't.

Why is that (i.e. is Chrome blocking the change somehow)? How can I get around this and change the icon? I'm sure there are apps for handling this, is there a way to do it without one?

Right click on the package, "show package content", then go in the "ressources" folder and change the icon there. The icon file is the .icns file.

• "Show Package Contents", Contents, Resources
• Replace app.icns with a new icon set
• Go to a Terminal and do touch /Applications/Google\ Chrome.app/ and killall Dock

Voilà