Google hires many people who are not from the US to come work in the US, so I don't think the 61.5% is reflective of their hiring pool.
*Ballpark white global population.
I'm also not saying that these numbers prove that Google does favor white workers. Only that they are not sufficient to disprove the idea.
It seems strange to put people in a position where showing a datapoint that would otherwise tend to refute a hypothesis (which IMO should not be assumed to be true in the first place) is not enough to be considered as evidence against the hypothesis being true.
The general trend I see in the community is that there's a strong belief that google, and by extension, the tech industry, is biased in favor of white workers.