Add Chromium environment application test support.

Add Chromium environment application test support.

Let Apptests run in Chromium and standalone environments.
Add mojo/public/cpp/application:test_support_standalone.
Add mojo/application/*main_chromium.cc and a GN target.
(MojoMain has base::AtExitManager not mojo::Environment)
Implement mojo/environment *DefaultRunLoop helper functions.

Use these for Chromium environment (w/base) Apptests:
  "//mojo/application",
  "//mojo/application:test_support",

Use these for standalone environment Apptests:
  "//mojo/public/cpp/application:standalone",
  "//mojo/public/cpp/application:test_support_standalone",

TODO: Add an example apptest for env chromium w/base use?
TODO: Use base::LaunchUnitTests, etc. in *main_chromium.cc.

BUG=392646
TEST="mojo_shell mojo:example_apptests" still works.
R=viettrungluu@chromium.org

Committed: https://chromium.googlesource.com/external/mojo/+/808cd0c8ead4ccb51b091d782fdc1368f607baad

[msw, 2014-10-31 20:08:38]

Patchset #5 (id:80001) has been deleted

[msw, 2014-10-31 20:15:57]

msw@chromium.org changed reviewers:
+ viettrungluu@chromium.org

[msw, 2014-10-31 20:18:22]

Hey Trung, please take a look; thanks!

[viettrungluu, 2014-10-31 20:26:46]

LGTM w/nits.

https://codereview.chromium.org/695593002/diff/120001/mojo/environment/defaul...
File mojo/environment/default_run_loop_impl.cc (right):

https://codereview.chromium.org/695593002/diff/120001/mojo/environment/defaul...
mojo/environment/default_run_loop_impl.cc:6: 
nit: #include "base/logging.h"

https://codereview.chromium.org/695593002/diff/120001/mojo/environment/defaul...
mojo/environment/default_run_loop_impl.cc:7: #include "base/compiler_specific.h"
Not needed (see below).

https://codereview.chromium.org/695593002/diff/120001/mojo/environment/defaul...
mojo/environment/default_run_loop_impl.cc:17: ALLOW_UNUSED_LOCAL(message_loop);
Not needed: not only is CHECK_EQ() always expanded, but even DCHECK_EQ() is
always expanded to something (i.e., always "uses" its arguments, even for
Release builds with DCHECKs disabled).

https://codereview.chromium.org/695593002/diff/120001/mojo/public/cpp/applica...
File mojo/public/cpp/application/BUILD.gn (right):

https://codereview.chromium.org/695593002/diff/120001/mojo/public/cpp/applica...
mojo/public/cpp/application/BUILD.gn:69: sources = [
"lib/application_test_main.cc", ]
nit: Probably you should be at least consistent within this file with respect to
the order of things (in particular, sources should probably come before
public_deps).

[msw, 2014-10-31 20:39:54]

Done; syncing and landing; thanks!

https://codereview.chromium.org/695593002/diff/120001/mojo/environment/defaul...
File mojo/environment/default_run_loop_impl.cc (right):

https://codereview.chromium.org/695593002/diff/120001/mojo/environment/defaul...
mojo/environment/default_run_loop_impl.cc:6: 
On 2014/10/31 20:26:46, viettrungluu wrote:
> nit: #include "base/logging.h"

Done.

https://codereview.chromium.org/695593002/diff/120001/mojo/environment/defaul...
mojo/environment/default_run_loop_impl.cc:7: #include "base/compiler_specific.h"
On 2014/10/31 20:26:46, viettrungluu wrote:
> Not needed (see below).

Done.

https://codereview.chromium.org/695593002/diff/120001/mojo/environment/defaul...
mojo/environment/default_run_loop_impl.cc:17: ALLOW_UNUSED_LOCAL(message_loop);
On 2014/10/31 20:26:45, viettrungluu wrote:
> Not needed: not only is CHECK_EQ() always expanded, but even DCHECK_EQ() is
> always expanded to something (i.e., always "uses" its arguments, even for
> Release builds with DCHECKs disabled).

Done. I suspected that might be the case, but wasn't sure; thanks!

https://codereview.chromium.org/695593002/diff/120001/mojo/public/cpp/applica...
File mojo/public/cpp/application/BUILD.gn (right):

https://codereview.chromium.org/695593002/diff/120001/mojo/public/cpp/applica...
mojo/public/cpp/application/BUILD.gn:69: sources = [
"lib/application_test_main.cc", ]
On 2014/10/31 20:26:46, viettrungluu wrote:
> nit: Probably you should be at least consistent within this file with respect
to
> the order of things (in particular, sources should probably come before
> public_deps).

Done (fixed here and 'test_support' above).

[msw, 2014-10-31 20:43:09]

Committed patchset #8 (id:160001) manually as
808cd0c8ead4ccb51b091d782fdc1368f607baad (presubmit successful).