Ensure tests check the return of SpawnChild() when they may wait without timeouts

Ensure tests check the return of SpawnChild() when they may wait without timeouts

Ensure that the result of SpawnChild() is consistently checked for unittests.
If an child fails to launch, SpawnChild() will return
base::kNullProcessHandle. Waiting on this handle is equivalent to waiting for
any child to terminate - and if there are no children, this may wait
indefinitely, causing the whole test executable to timeout after 10 minutes.

BUG=none
TEST=none


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=91430

[Ryan Sleevi, 2011-07-01 23:43:32]

brettw: Since you're an OWNER in both, would you mind taking a look?

I'm using ASSERT_TRUE(...), rather than ASSERT_NE(base::kNullProcessHandle,
...), as that is the existing pattern throughout the codebase. This works for
all the platforms, since kNullProcessHandle is false-equivalent, but I can
change to ASSERT_NE if you'd rather.

The motivator for this was related to http://crbug.com/87970 - the Mac sandbox
tests took 600 seconds to timeout when that flakiness was encountered. It'd be
more useful if it failed faster - hence the ASSERTs.

[brettw, 2011-07-02 15:47:20]

LGTM

[commit-bot: I haz the power, 2011-07-02 19:44:24]

Try job failure for 7304008-2002 (retry) on mac for step "compile" (clobber
build).
It's a second try, previously, step "compile" failed.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=mac&number...

[commit-bot: I haz the power, 2011-07-02 22:01:16]

Change committed as 91430