Have LifecycleContext::lifecycleNotifier() return a reference

Have LifecycleContext::lifecycleNotifier() return a reference

Have LifecycleContext::lifecycleNotifier() return a reference instead
of a pointer as it can never return null. This makes the calling
code look safer.

R=adamk
BUG=

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=160456

[adamk, 2013-10-23 21:49:32]

Handing off to morrita, as I'm not sure exactly where all this Lifecycle stuff
is headed; there seems to be a lot of createLifecycleNotifier methods but I
don't see  alot of callers...

[Hajime Morrita, 2013-10-24 04:16:42]

LGTM. This is fine.
Please update the patch. I just landed one that conflicts with this :-/

[Hajime Morrita, 2013-10-24 04:17:52]

LTGM. This is fine.
Please update the patch to ToT. I just landed one that conflict with this :-/

[Hajime Morrita, 2013-10-24 04:18:19]

Hmm. for some reason I cannot comment on this issue.

[Hajime Morrita, 2013-10-24 04:18:47]

LTGM. This is fine.
Please update the patch to ToT. I just landed one that conflict with this :-/

[Hajime Morrita, 2013-10-24 04:19:10]

Ooops. Something wrong is happening ... Sorry for the noise.

[commit-bot: I haz the power, 2013-10-24 14:22:12]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/ch.dumez@samsung.com/38143002/130001

[commit-bot: I haz the power, 2013-10-24 15:37:13]

Change committed as 160456