Investor appetite in food delivery companies is growing, notwithstanding a rash of customer complaints about how these startups pay contract workers. On Thursday, DoorDash announced it had raised another $400 million in a Series F funding round led by Temasek and Dragoneer Investment Group. The cash infusion brings DoorDash’s total capital raised to $1.4 billion, of which $978 million came from funding rounds in the last year.