Even taking into account the lowest of your figures of 3.6% black graduates in Computer Science, this would still leave the 1% rate of black employees at Facebook substantially lower than their potential hiring pool. Also consider that Facebook reported that their percentage of black employees among non-tech workers is not any better at a measly 2%. Considering that blacks represent 10% of all college graduates, this would imply that your average black college graduate is 5 times less likely to be hired at Facebook than a person of different ethnicity.
Sorry if that doesn't give your axes a nice fine edge, folks, but the likes of Google, Yahoo, and Facebook don't hire only misogynist racists for their HR departments - In fact, all three soundly beat the above graduation rates, making them arguably biased against hiring white males.
Their hiring numbers for women may be in line with graduation rates in computer science, but their minority hiring is significantly lower than graduation rates, no matter how you look at the numbers. And given their large employee sizes, this a statistically significant hiring bias. Turning a blind eye to the statistical reality won't make the problem go away.