[dev.cc] build: skip API checks on Windows too (not just Unix)
[dev.cc] build: skip API checks on Windows too (not just Unix)

TBR=brainman
CC=golang-codereviews
https://codereview.appspot.com/175490043

d0f/go-zh,webfd/go-zh,bryanxu/go-zh,bryanxu/go-zh,d0f/go-zh,d0f/go-zh,d0f/go-zh,webfd/go-zh,webfd/go-zh,d0f/go-zh,webfd/go-zh,webfd/go-zh,bryanxu/go-zh,bryanxu/go-zh,bryanxu/go-zh,webfd/go-zh,webfd/go-zh,d0f/go-zh,bryanxu/go-zh,bryanxu/go-zh,d0f/go-zh,d0f/go-zh,bryanxu/go-zh,webfd/go-zh