Row Highlighter for Gmail and Inbox for Chrome
More About Row Highlighter for Gmail and Inbox
Starting from version 1.1, you can customize the colors! :-)
Credits goes to stasnikiforov for the style format, and to Jhon for the idea (http://userstyles.org/styles/4725).
You might also be interested in this extension: https://chrome.google.com/extensions/detail/johdeoloijidhejmalfkpchbihbiamph