Make InitializeMojo() idempotent.

Make InitializeMojo() idempotent.

For tests, there are some difficulties to guarantee it being called just once.

This is a retake of https://codereview.chromium.org/866973004/,
which didn't work with some tests.

R=agl@chromium.org, sky@chromium.org
TEST=RenderThreadImplBrowserTest
BUG=

Committed: https://crrev.com/e7522209c42fda9d0ded8e766bbe79cc187c3a30
Cr-Commit-Position: refs/heads/master@{#313139}

[agl, 2015-01-26 19:08:50]

Why not make the underlying InitializeMojo() call Just Work, even if called
multiple times like other init functions?

In order to ensure that a function runs only once, see base/lazy_instance.h.

[Hajime Morrita, 2015-01-26 19:55:00]

On 2015/01/26 19:08:50, agl wrote:
> Why not make the underlying InitializeMojo() call Just Work, even if called
> multiple times like other init functions?
> 
> In order to ensure that a function runs only once, see base/lazy_instance.h.
That's right. I made the change. PTAL?

[agl, 2015-01-26 20:02:47]

lgtm

https://codereview.chromium.org/872973003/diff/20001/content/app/mojo/mojo_in...
File content/app/mojo/mojo_init.cc (right):

https://codereview.chromium.org/872973003/diff/20001/content/app/mojo/mojo_in...
content/app/mojo/mojo_init.cc:27: base::LazyInstance<MojoInitializer>
mojo_initializer;
I suspect that you want base::LazyInstance<MojoInitializer>::Leaky. See header
file for details.

[sky, 2015-01-26 20:10:30]

LGTM

[Hajime Morrita, 2015-01-26 20:32:54]

On 2015/01/26 20:02:47, agl wrote:
> lgtm
> 
>
https://codereview.chromium.org/872973003/diff/20001/content/app/mojo/mojo_in...
> File content/app/mojo/mojo_init.cc (right):
> 
>
https://codereview.chromium.org/872973003/diff/20001/content/app/mojo/mojo_in...
> content/app/mojo/mojo_init.cc:27: base::LazyInstance<MojoInitializer>
> mojo_initializer;
> I suspect that you want base::LazyInstance<MojoInitializer>::Leaky. See header
> file for details.
Right. No need for the destructor.

[Hajime Morrita, 2015-01-26 20:33:27]

The CQ bit was checked by morrita@chromium.org

[commit-bot: I haz the power, 2015-01-26 20:34:09]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/872973003/40001

[commit-bot: I haz the power, 2015-01-26 21:27:05]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-01-26 21:28:31]

Patchset 3 (id:??) landed as
https://crrev.com/e7522209c42fda9d0ded8e766bbe79cc187c3a30
Cr-Commit-Position: refs/heads/master@{#313139}