Add a convenience typedef LazyInstance<T>::Leaky to avoid repeating T.

Add a convenience typedef LazyInstance<T>::Leaky to avoid repeating T.

Converted the first 20 or so hits for LeakyLazyInstanceTraits on codesearch to
demonstrate the benefit at callsites.  The real change is base/lazy_instance.h;
everything else is example.

BUG=none
TEST=none

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=118754

[Ami GONE FROM CHROMIUM, 2012-01-19 21:15:40]

This is a speculative CL.

Evan: WDYT?

[Evan Martin, 2012-01-19 21:23:53]

Every lazy instance we have is a singleton, with all the attendant annoying
problems with singletons.  I kinda feel like making singletons should be
painful.  But maybe I'm just grumpy today.

[Ami GONE FROM CHROMIUM, 2012-01-20 17:10:56]

Are you materially less grumpy today (about this CL)?
(my grumpmeter technology only asks once; if you still don't think it's
worthwhile today I'll close this review unsubmitted)

-a

On Thu, Jan 19, 2012 at 1:23 PM, <evan@chromium.org> wrote:

> Every lazy instance we have is a singleton, with all the attendant annoying
> problems with singletons.  I kinda feel like making singletons should be
> painful.  But maybe I'm just grumpy today.
>
>
https://chromiumcodereview.**appspot.com/9192024/<https://chromiumcodereview....
>

[Evan Martin, 2012-01-20 17:21:53]

LGTM

[Ami GONE FROM CHROMIUM, 2012-01-20 17:26:43]

thestig/wtc/kbr: can I get OWNERS-stamps from each of you for your resp. parts
of the codebase?

[Ken Russell (switch to Gerrit), 2012-01-20 18:15:25]

GPU changes LGTM

[wtc, 2012-01-21 00:51:00]

LGTM.  I only reviewed base, crypto, and net.

https://chromiumcodereview.appspot.com/9192024/diff/1/base/lazy_instance.h
File base/lazy_instance.h (right):

https://chromiumcodereview.appspot.com/9192024/diff/1/base/lazy_instance.h#ne...
base/lazy_instance.h:76: // Use LazyInstance<T>::Leaky for a less-verbose
call-site typedef.

Nit: would be nice to give an example.  Before I saw your
change to base/lazy_instance_unittest.cc, I didn't understand
this comment completely.

Nit: Is it possible for this convenience typedef to be
named LeakyLazyInstance<T>?

https://chromiumcodereview.appspot.com/9192024/diff/1/net/ocsp/nss_ocsp.cc
File net/ocsp/nss_ocsp.cc (right):

https://chromiumcodereview.appspot.com/9192024/diff/1/net/ocsp/nss_ocsp.cc#ne...
net/ocsp/nss_ocsp.cc:91: g_ocsp_io_loop = LAZY_INSTANCE_INITIALIZER;

Nit: could you reformat this as

  base::LazyInstance<OCSPIOLoop>::Leaky g_ocsp_io_loop =
      LAZY_INSTANCE_INITIALIZER;

and in other places where this is possible?  Probably not
worth the trouble.

[Ami GONE FROM CHROMIUM, 2012-01-21 01:22:29]

https://chromiumcodereview.appspot.com/9192024/diff/1/base/lazy_instance.h
File base/lazy_instance.h (right):

https://chromiumcodereview.appspot.com/9192024/diff/1/base/lazy_instance.h#ne...
base/lazy_instance.h:76: // Use LazyInstance<T>::Leaky for a less-verbose
call-site typedef.
On 2012/01/21 00:51:01, wtc wrote:
> 
> Nit: would be nice to give an example.  Before I saw your
> change to base/lazy_instance_unittest.cc, I didn't understand
> this comment completely.

Done.

> Nit: Is it possible for this convenience typedef to be
> named LeakyLazyInstance<T>?

Not until we adopt c++11 and get template typedefs.
I tried being tricksy with subclassing, but that breaks brace initialization.

https://chromiumcodereview.appspot.com/9192024/diff/1/net/ocsp/nss_ocsp.cc
File net/ocsp/nss_ocsp.cc (right):

https://chromiumcodereview.appspot.com/9192024/diff/1/net/ocsp/nss_ocsp.cc#ne...
net/ocsp/nss_ocsp.cc:91: g_ocsp_io_loop = LAZY_INSTANCE_INITIALIZER;
On 2012/01/21 00:51:01, wtc wrote:
> 
> Nit: could you reformat this as
> 
>   base::LazyInstance<OCSPIOLoop>::Leaky g_ocsp_io_loop =
>       LAZY_INSTANCE_INITIALIZER;
> 
> and in other places where this is possible?  Probably not
> worth the trouble.

I intentionally didn't as there were callsites that could have done that but
didn't (style was mixed).  Opted for least-change.

[wtc, 2012-01-21 01:47:36]

LGTM.  Thanks.

https://chromiumcodereview.appspot.com/9192024/diff/12002/base/lazy_instance.h
File base/lazy_instance.h (right):

https://chromiumcodereview.appspot.com/9192024/diff/12002/base/lazy_instance....
base/lazy_instance.h:77: // LazyInstance<MyType>::Leaky my_leaky_lazy_instance;

I suggest also showing the verbose form it replaces:

LazyInstance<MyType, LeakyLazyInstanceTraits<Type> > my_leaky_lazy_instance;

Including base:: will show the typical call-sites outside
the base namespace.

[Ami GONE FROM CHROMIUM, 2012-01-21 04:49:20]

https://chromiumcodereview.appspot.com/9192024/diff/12002/base/lazy_instance.h
File base/lazy_instance.h (right):

https://chromiumcodereview.appspot.com/9192024/diff/12002/base/lazy_instance....
base/lazy_instance.h:77: // LazyInstance<MyType>::Leaky my_leaky_lazy_instance;
On 2012/01/21 01:47:36, wtc wrote:
> 
> I suggest also showing the verbose form it replaces:
> 
> LazyInstance<MyType, LeakyLazyInstanceTraits<Type> > my_leaky_lazy_instance;
> 
> Including base:: will show the typical call-sites outside
> the base namespace.

Done.

[Lei Zhang, 2012-01-23 20:38:44]

printing/ LGTM

[commit-bot: I haz the power, 2012-01-23 20:47:41]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/fischman@chromium.org/9192024/8002

[commit-bot: I haz the power, 2012-01-23 20:47:50]

Can't apply patch for file base/win/sampling_profiler.cc.
While running patch -p1 --forward --force;
patching file base/win/sampling_profiler.cc
Hunk #1 FAILED at 104.
1 out of 1 hunk FAILED -- saving rejects to file
base/win/sampling_profiler.cc.rej

[commit-bot: I haz the power, 2012-01-23 20:53:58]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/fischman@chromium.org/9192024/18001

[commit-bot: I haz the power, 2012-01-23 22:29:16]

Can't apply patch for file base/debug/trace_event.cc.
While running patch -p1 --forward --force;
patching file base/debug/trace_event.cc
Hunk #1 FAILED at 63.
1 out of 1 hunk FAILED -- saving rejects to file base/debug/trace_event.cc.rej