I'm pretty sure this isn't intentional. No one at Google is going to be using a crap monitor. I've used similar colors in business software before. It wasn't until I was at a conference and saw our software on a crappy screen that I realized the required field color was white on some monitors.

Sorry, but you can't tell me that any aspect on the Google search results page, of all the pages on the internet, isn't fully intentional.

On my shitty laptop's screen they literally are indistinguishable.