You can use "Extensions Reloader" for Chrome:
Reload all unpacked extensions using the extension's toolbar button or by browsing to "http://reload.extensions"
If you've ever developed a Chrome extension, you might have wanted to
automate the process of reloading your unpacked extension without the
need of going through the extensions page.
"Extensions Reloader" allows you to reload all unpacked extensions
using 2 ways:
1 - The extension's toolbar button.
2 - Browsing to "http://reload.extensions".
The toolbar icon will reload unpacked extensions using a single click.
The "reload by browsing" is intended for automating the reload process
using "post build" scripts - just add a browse to
"http://reload.extensions" using Chrome to your script, and you'll
have a refreshed Chrome window.