Just like all.bash passes flags to make.bash, I think it makes
sense that naclmake.bash and nacltest.bash do so as well. For
example, on a slow machine I can do "./nacltest.bash -v" to see
the build progress.

Change-Id: Id766dd590e6b83e8b5345822580dc1b05eac8ea3
Reviewed-on: https://go-review.googlesource.com/93117
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>