Often the slow commands (errorprone happens to be particularly bad)
print a lot, so this should make it easier to find the error without
lots of scrolling.
This doesn't attempt to parse the output and re-display errors, so
if a command prints a thousand warnings with one error in the middle,
it'll still be hard to find the error.
Bug: 277114612
Test: cd build/soong/ui/terminal ; go test
Change-Id: I6c8285fc2c6e4fc345de57b2c15bc5e7d46b1d1f
eadb0fbee0