I think it makes sense to DCHECK and avoid calling Init() multiple times.
I don't know much about the LaunchTwice that you mentioned above, do you mean https://codesearch.chromium.org/chromium/src/content/public/test/browser_test_base.h?l=71&ct=xref_jump_to_def

+CC rockot who knows better about the edk API

Not expected and not OK. We should DCHECK. As for browser tests, we call Init very early in content initialization, so I'm surprised any test code can cause that code path to be hit twice.

Great to know. Thank you for advice.
Let me give it a try to look into each failure.

So, I categorized failures to four cases (two leaks in prod, and two for tests):
- nacl_helper leaks (crrev.com/2622423004)
- service_process leaks (crrev.com/2624263005)
- chromecast tests leaks (crrev.com/2627753007), and
- service_manager tests leaks (crrev.com/2628333002).

So, before adding DCHECK, these need to be fixed.
# Considering prod leaks, I set P3 -> P2.

The fixing approach above is;
- Keep relying on content::InitilizeMojo().
  - Remove mojo::edk::Init() conflicting with it.
  - For NaClMain case, NaClWin64Main does something compatible with ContentMain(), so it is moved to there.
- BrowserTest::SetUp triggers InitializeMojo(), so relying on it.
- For unittests, mojo::edk::Init()/InitIPCSupport() are called in main() (or main compatible function).

Once these four fixes are landed, we can then add DCHECK, like WIP crrev.com/2625363004, so that in future we can trap the case.

yzshen@, rockot@, could you kindly take a look at these WIP CLs?
If these are good directions to fix, I'm happy to send them to code reviews.
If there needs some big direction change, would you mind to take it over?

Thanks!

I would prefer that we eliminate InitializeMojo(). I don't like the idea of
using a lazy static initializer to essentially hide accidental duplicate
initialization. It should not be difficult for us to ensure that we have
consistent ownership of Mojo init/shutdown in our various binaries.


- For unittests, mojo::edk::Init()/InitIPCSupport() are called in main()