Add GetWakeLockWithoutContext() in WakeLockContextProvider mojo interface.

Add GetWakeLockWithoutContext() in WakeLockContextProvider mojo interface.
    
1) Add GetWakeLockWithoutContext in WakeLockContextProvider.
2) Rename WakeLockContextProvider to WakeLockProvider as it provides both WakeLockService and WakeLockContext.
3) Convert download_request_core to be client of wakelock.

BUG=689410
TBR=jam@chromium.org, for mechanical changes in //content/browser/wake_lock/wake_lock_context_host{.h|.cc}

Review-Url: https://codereview.chromium.org/2874013002
Cr-Commit-Position: refs/heads/master@{#471629}
Committed: https://chromium.googlesource.com/chromium/src/+/2d8b867dfc360643d87634931521e9c5a39594fc

[ke.he, 2017-05-10 14:20:17]

The CQ bit was checked by ke.he@intel.com to run a CQ dry run

[commit-bot: I haz the power, 2017-05-10 14:21:04]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-10 14:43:21]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-05-10 14:43:22]

Dry run: Try jobs failed on following builders:
  cast_shell_linux on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/cast_shell_linu...)

[ke.he, 2017-05-11 04:17:27]

The CQ bit was checked by ke.he@intel.com to run a CQ dry run

[commit-bot: I haz the power, 2017-05-11 04:19:02]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-11 04:55:26]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-05-11 04:55:27]

Dry run: Try jobs failed on following builders:
  linux_android_rel_ng on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/linux_androi...)

[ke.he, 2017-05-11 08:02:55]

The CQ bit was checked by ke.he@intel.com to run a CQ dry run

[commit-bot: I haz the power, 2017-05-11 08:03:26]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[ke.he, 2017-05-11 08:22:20]

Description was changed from

==========
Add GetUnassociatedWakeLockContext in WakeLockContextProvider mojo interface.

1) Add GetUnassociatedWakeLockContext in WakeLockContextProvider.
2) Convert download_request_core to be client of wakelock.

BUG=
==========

to

==========
Add GetUnassociatedWakeLockContext in WakeLockContextProvider mojo interface.

1) Add GetUnassociatedWakeLockContext in WakeLockContextProvider.
2) Convert download_request_core to be client of wakelock.

BUG=689410
==========

[commit-bot: I haz the power, 2017-05-11 10:10:16]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-05-11 10:10:17]

Dry run: Try jobs failed on following builders:
  win_chromium_x64_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_...)

[ke.he, 2017-05-11 12:39:46]

ke.he@intel.com changed reviewers:
+ blundell@chromium.org

[ke.he, 2017-05-11 12:39:47]

Colin, PTAL. Not sure should I split the download client into a separate CL?

Thanks.

[blundell, 2017-05-11 15:42:40]

Thanks!

https://codereview.chromium.org/2874013002/diff/40001/device/wake_lock/public...
File device/wake_lock/public/interfaces/wake_lock_context_provider.mojom
(right):

https://codereview.chromium.org/2874013002/diff/40001/device/wake_lock/public...
device/wake_lock/public/interfaces/wake_lock_context_provider.mojom:13: //
Android (see WakeLockContextCallback).
Let's note that context_ids must be >=0, and DCHECK that in the impl.

https://codereview.chromium.org/2874013002/diff/40001/device/wake_lock/public...
device/wake_lock/public/interfaces/wake_lock_context_provider.mojom:17:
GetUnassociatedWakeLockContext(WakeLockContext& context);
Looking at the client usage, I now think that it would be better for this method
to be:

GetWakeLockWithoutContext(type, reason, description, WakeLockService&
wake_lock);

That way clients won't need to go through the dance of getting a context first.

Let's add to the comment here:

// Gets a Wake Lock outside of any context. This method can be used // if the
client does not have any context available (e.g., is not // within the context
of a WebContents). However, note that the resulting
// Wake Lock will not have any effect on Android.

[ke.he, 2017-05-11 16:08:05]

https://codereview.chromium.org/2874013002/diff/40001/device/wake_lock/public...
File device/wake_lock/public/interfaces/wake_lock_context_provider.mojom
(right):

https://codereview.chromium.org/2874013002/diff/40001/device/wake_lock/public...
device/wake_lock/public/interfaces/wake_lock_context_provider.mojom:17:
GetUnassociatedWakeLockContext(WakeLockContext& context);
On 2017/05/11 15:42:40, blundell wrote:
> Looking at the client usage, I now think that it would be better for this
method
> to be:
> 
> GetWakeLockWithoutContext(type, reason, description, WakeLockService&
> wake_lock);
> 
> That way clients won't need to go through the dance of getting a context
first.
> 
> Let's add to the comment here:
> 
> // Gets a Wake Lock outside of any context. This method can be used // if the
> client does not have any context available (e.g., is not // within the context
> of a WebContents). However, note that the resulting
> // Wake Lock will not have any effect on Android.

Thanks. I will update them tomorrow :D

In this way this interface provides both WakeLockContext and WakeLockService. I
feel maybe we need to change the interface name "context_provider" too ?

[blundell, 2017-05-11 16:13:26]

On 2017/05/11 16:08:05, ke.he wrote:
>
https://codereview.chromium.org/2874013002/diff/40001/device/wake_lock/public...
> File device/wake_lock/public/interfaces/wake_lock_context_provider.mojom
> (right):
> 
>
https://codereview.chromium.org/2874013002/diff/40001/device/wake_lock/public...
> device/wake_lock/public/interfaces/wake_lock_context_provider.mojom:17:
> GetUnassociatedWakeLockContext(WakeLockContext& context);
> On 2017/05/11 15:42:40, blundell wrote:
> > Looking at the client usage, I now think that it would be better for this
> method
> > to be:
> > 
> > GetWakeLockWithoutContext(type, reason, description, WakeLockService&
> > wake_lock);
> > 
> > That way clients won't need to go through the dance of getting a context
> first.
> > 
> > Let's add to the comment here:
> > 
> > // Gets a Wake Lock outside of any context. This method can be used // if
the
> > client does not have any context available (e.g., is not // within the
context
> > of a WebContents). However, note that the resulting
> > // Wake Lock will not have any effect on Android.
> 
> Thanks. I will update them tomorrow :D
> 
> In this way this interface provides both WakeLockContext and WakeLockService.
I
> feel maybe we need to change the interface name "context_provider" too ?

Great point! Let's call it WakeLockProvider.

[ke.he, 2017-05-12 05:35:15]

The CQ bit was checked by ke.he@intel.com to run a CQ dry run

[commit-bot: I haz the power, 2017-05-12 05:35:45]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-12 06:16:28]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-05-12 06:16:29]

Dry run: Try jobs failed on following builders:
  cast_shell_linux on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/cast_shell_linu...)

[ke.he, 2017-05-12 08:04:51]

The CQ bit was checked by ke.he@intel.com to run a CQ dry run

[commit-bot: I haz the power, 2017-05-12 08:05:12]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-12 09:02:03]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-05-12 09:02:06]

Dry run: Try jobs failed on following builders:
  linux_android_rel_ng on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/linux_androi...)

[ke.he, 2017-05-12 10:05:49]

The CQ bit was checked by ke.he@intel.com to run a CQ dry run

[commit-bot: I haz the power, 2017-05-12 10:06:05]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-12 11:10:53]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-05-12 11:10:54]

Dry run: Try jobs failed on following builders:
  linux_chromium_chromeos_ozone_rel_ng on master.tryserver.chromium.linux
(JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[ke.he, 2017-05-12 11:45:08]

The CQ bit was checked by ke.he@intel.com to run a CQ dry run

[commit-bot: I haz the power, 2017-05-12 11:45:31]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-12 12:09:32]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-05-12 12:09:33]

Dry run: This issue passed the CQ dry run.

[ke.he, 2017-05-12 12:23:53]

Description was changed from

==========
Add GetUnassociatedWakeLockContext in WakeLockContextProvider mojo interface.

1) Add GetUnassociatedWakeLockContext in WakeLockContextProvider.
2) Convert download_request_core to be client of wakelock.

BUG=689410
==========

to

==========
Add GetWakeLockWithoutContext() in WakeLockContextProvider mojo interface.
    
1) Add GetWakeLockWithoutContext in WakeLockContextProvider.
2) Rename WakeLockContextProvider to WakeLockProvider as it provides both
WakeLockService and WakeLockContext.
3) Convert download_request_core to be client of wakelock.

BUG=689410
==========

[ke.he, 2017-05-12 12:24:24]

Colin, PTAL. Thanks.

https://codereview.chromium.org/2874013002/diff/40001/device/wake_lock/public...
File device/wake_lock/public/interfaces/wake_lock_context_provider.mojom
(right):

https://codereview.chromium.org/2874013002/diff/40001/device/wake_lock/public...
device/wake_lock/public/interfaces/wake_lock_context_provider.mojom:13: //
Android (see WakeLockContextCallback).
On 2017/05/11 15:42:40, blundell wrote:
> Let's note that context_ids must be >=0, and DCHECK that in the impl.

Done.

https://codereview.chromium.org/2874013002/diff/40001/device/wake_lock/public...
device/wake_lock/public/interfaces/wake_lock_context_provider.mojom:17:
GetUnassociatedWakeLockContext(WakeLockContext& context);
On 2017/05/11 15:42:40, blundell wrote:
> Looking at the client usage, I now think that it would be better for this
method
> to be:
> 
> GetWakeLockWithoutContext(type, reason, description, WakeLockService&
> wake_lock);
> 
> That way clients won't need to go through the dance of getting a context
first.
> 
> Let's add to the comment here:
> 
> // Gets a Wake Lock outside of any context. This method can be used // if the
> client does not have any context available (e.g., is not // within the context
> of a WebContents). However, note that the resulting
> // Wake Lock will not have any effect on Android.

Done.

[blundell, 2017-05-12 12:42:18]

LGTM!

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
File content/browser/download/download_request_core.cc (right):

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
content/browser/download/download_request_core.cc:35: #include
"device/wake_lock/public/interfaces/wake_lock_context.mojom.h"
Not needed now.

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
content/browser/download/download_request_core.cc:207: if (connector) {
I think we should elide this instead you have evidence that it's needed. If it's
needed, we should document why (e.g. "// null in testing contexts").

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
File content/browser/download/download_request_core.h (right):

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
content/browser/download/download_request_core.h:145: // Keeps the system from
sleeping while this is alive. If the
"while this is alive" isn't correct anymore. Maybe just "Used to keep the system
from sleeping while a download is ongoing." as the first sentence of this
comment.

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
content/browser/download/download_request_core.h:146: // system enters power
saving mode while a request is alive, it can cause the
"request" is ambiguous now. Let's say "URLRequest" instead.

https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/public...
File device/wake_lock/public/interfaces/README.md (right):

https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/public...
device/wake_lock/public/interfaces/README.md:19: necessary/employed.
Let's add comments here about the usage model outside of a context, including
calling out that that means that the Wake Lock will not be functional on
Android.

https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/wake_l...
File device/wake_lock/wake_lock_service_impl.cc (right):

https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/wake_l...
device/wake_lock/wake_lock_service_impl.cc:137: return;
Maybe we should LOG(ERROR) here, as if the client is using a wake lock to
prevent display sleep on Android and isn't passing a context ID, they're quite
likely not getting the behavior they want.

[ke.he, 2017-05-12 15:32:43]

>
https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/wake_l...
> File device/wake_lock/wake_lock_service_impl.cc (right):
> 
>
https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/wake_l...
> device/wake_lock/wake_lock_service_impl.cc:137: return;
> Maybe we should LOG(ERROR) here, as if the client is using a wake lock to
> prevent display sleep on Android and isn't passing a context ID, they're quite
> likely not getting the behavior they want.

I suddenly think that: If client is using a wake lock with
"PreventAppSuspension" type on Android. We cannot deem it as ERROR, it is a good
behavior, right? Because only the type "PreventDisplaySleep" needs the
context_id when calls InitDisplaySleepBlocker("native_view").

So I think it is OK for client to use GetWakeLockWithoutContext(
"PreventAppSuspension", ...) to request wakelock on Android. If it is OK, We
need to correct the comments of GetWakeLockWithoutContext() in
wake_lock_provider.mojom too, where it says "has no effect for Android"

[ke.he, 2017-05-12 15:53:18]

On 2017/05/12 15:32:43, ke.he wrote:
> >
>
https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/wake_l...
> > File device/wake_lock/wake_lock_service_impl.cc (right):
> > 
> >
>
https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/wake_l...
> > device/wake_lock/wake_lock_service_impl.cc:137: return;
> > Maybe we should LOG(ERROR) here, as if the client is using a wake lock to
> > prevent display sleep on Android and isn't passing a context ID, they're
quite
> > likely not getting the behavior they want.
> 
> I suddenly think that: If client is using a wake lock with
> "PreventAppSuspension" type on Android. We cannot deem it as ERROR, it is a
good
> behavior, right? Because only the type "PreventDisplaySleep" needs the
> context_id when calls InitDisplaySleepBlocker("native_view").
> 
> So I think it is OK for client to use GetWakeLockWithoutContext(
> "PreventAppSuspension", ...) to request wakelock on Android. If it is OK, We
> need to correct the comments of GetWakeLockWithoutContext() in
> wake_lock_provider.mojom too, where it says "has no effect for Android"

Sorry, Ignore my above comments, the android doesn't support
"PreventAppSuspension"!

[ke.he, 2017-05-12 16:06:30]

The CQ bit was checked by ke.he@intel.com to run a CQ dry run

[commit-bot: I haz the power, 2017-05-12 16:07:20]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[ke.he, 2017-05-12 16:09:37]

ke.he@intel.com changed reviewers:
+ dtrainor@chromium.org, tsepez@chromium.org

[ke.he, 2017-05-12 16:09:39]

Hi, Dtrainor@, PTAL on the //content/browser/download.
TOM, PTAL on the mojom files.  Thanks!

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
File content/browser/download/download_request_core.cc (right):

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
content/browser/download/download_request_core.cc:35: #include
"device/wake_lock/public/interfaces/wake_lock_context.mojom.h"
On 2017/05/12 12:42:18, blundell wrote:
> Not needed now.

Done.

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
content/browser/download/download_request_core.cc:207: if (connector) {
On 2017/05/12 12:42:18, blundell wrote:
> I think we should elide this instead you have evidence that it's needed. If
it's
> needed, we should document why (e.g. "// null in testing contexts").

I noticed in wake_lock_context_host.cc, line 35, there is a comments: "in some
testing contexts, the service manager connection isn't initialized". I think
here is the same case, the |connector| here is a clone from service manager
connection. I'll add a comments.

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
File content/browser/download/download_request_core.h (right):

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
content/browser/download/download_request_core.h:145: // Keeps the system from
sleeping while this is alive. If the
On 2017/05/12 12:42:18, blundell wrote:
> "while this is alive" isn't correct anymore. Maybe just "Used to keep the
system
> from sleeping while a download is ongoing." as the first sentence of this
> comment.

Done.

https://codereview.chromium.org/2874013002/diff/80001/content/browser/downloa...
content/browser/download/download_request_core.h:146: // system enters power
saving mode while a request is alive, it can cause the
On 2017/05/12 12:42:18, blundell wrote:
> "request" is ambiguous now. Let's say "URLRequest" instead.

Done.

https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/public...
File device/wake_lock/public/interfaces/README.md (right):

https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/public...
device/wake_lock/public/interfaces/README.md:19: necessary/employed.
On 2017/05/12 12:42:18, blundell wrote:
> Let's add comments here about the usage model outside of a context, including
> calling out that that means that the Wake Lock will not be functional on
> Android.

Done.

https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/wake_l...
File device/wake_lock/wake_lock_service_impl.cc (right):

https://codereview.chromium.org/2874013002/diff/80001/device/wake_lock/wake_l...
device/wake_lock/wake_lock_service_impl.cc:137: return;
On 2017/05/12 12:42:18, blundell wrote:
> Maybe we should LOG(ERROR) here, as if the client is using a wake lock to
> prevent display sleep on Android and isn't passing a context ID, they're quite
> likely not getting the behavior they want.

Done.

[ke.he, 2017-05-12 16:13:22]

Description was changed from

==========
Add GetWakeLockWithoutContext() in WakeLockContextProvider mojo interface.
    
1) Add GetWakeLockWithoutContext in WakeLockContextProvider.
2) Rename WakeLockContextProvider to WakeLockProvider as it provides both
WakeLockService and WakeLockContext.
3) Convert download_request_core to be client of wakelock.

BUG=689410
==========

to

==========
Add GetWakeLockWithoutContext() in WakeLockContextProvider mojo interface.
    
1) Add GetWakeLockWithoutContext in WakeLockContextProvider.
2) Rename WakeLockContextProvider to WakeLockProvider as it provides both
WakeLockService and WakeLockContext.
3) Convert download_request_core to be client of wakelock.

BUG=689410
TBR=jam@chromium.org, for mechanical changes in
//content/browser/wake_lock/wake_lock_context_host{.h|.cc}
==========

[ke.he, 2017-05-12 16:13:22]

ke.he@intel.com changed reviewers:
+ jam@chromium.org

[Tom Sepez, 2017-05-12 16:24:39]

lgtm

[commit-bot: I haz the power, 2017-05-12 18:45:47]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-05-12 18:45:48]

Dry run: Try jobs failed on following builders:
  linux_android_rel_ng on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/linux_androi...)

[jam, 2017-05-12 19:52:22]

lgtm

[David Trainor- moved to gerrit, 2017-05-14 05:52:40]

content/browser/download lgtm % nit

https://codereview.chromium.org/2874013002/diff/100001/content/browser/downlo...
File content/browser/download/download_request_core.cc (right):

https://codereview.chromium.org/2874013002/diff/100001/content/browser/downlo...
content/browser/download/download_request_core.cc:206: // |connector| might be
nullptr in some testing contexts, in which thei
thei -> the?

[ke.he, 2017-05-14 09:47:55]

The CQ bit was checked by ke.he@intel.com to run a CQ dry run

[commit-bot: I haz the power, 2017-05-14 09:48:01]

Dry run: CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-05-14 11:54:57]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-05-14 11:54:58]

Dry run: This issue passed the CQ dry run.

[ke.he, 2017-05-14 12:04:10]

The CQ bit was checked by ke.he@intel.com

[ke.he, 2017-05-14 12:04:10]

The patchset sent to the CQ was uploaded after l-g-t-m from
blundell@chromium.org, tsepez@chromium.org, dtrainor@chromium.org,
jam@chromium.org
Link to the patchset: https://codereview.chromium.org/2874013002/#ps120001
(title: "Add GetWakeLockWithoutContext in WakeLockContextProvider mojo
interface.")

[commit-bot: I haz the power, 2017-05-14 12:04:23]

CQ is trying da patch.

Follow status at:
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[ke.he, 2017-05-14 12:05:00]

Thanks.

https://codereview.chromium.org/2874013002/diff/100001/content/browser/downlo...
File content/browser/download/download_request_core.cc (right):

https://codereview.chromium.org/2874013002/diff/100001/content/browser/downlo...
content/browser/download/download_request_core.cc:206: // |connector| might be
nullptr in some testing contexts, in which thei
On 2017/05/14 05:52:40, David Trainor-ping if over 24h wrote:
> thei -> the?

Done.

[commit-bot: I haz the power, 2017-05-14 12:09:45]

CQ is committing da patch.

Bot data: {"patchset_id": 120001, "attempt_start_ts": 1494763450361320,
"parent_rev": "064e1830e9ed3d48d6342b26fcfd4335d6e09bfb", "commit_rev":
"2d8b867dfc360643d87634931521e9c5a39594fc"}

[commit-bot: I haz the power, 2017-05-14 12:09:58]

Description was changed from

==========
Add GetWakeLockWithoutContext() in WakeLockContextProvider mojo interface.
    
1) Add GetWakeLockWithoutContext in WakeLockContextProvider.
2) Rename WakeLockContextProvider to WakeLockProvider as it provides both
WakeLockService and WakeLockContext.
3) Convert download_request_core to be client of wakelock.

BUG=689410
TBR=jam@chromium.org, for mechanical changes in
//content/browser/wake_lock/wake_lock_context_host{.h|.cc}
==========

to

==========
Add GetWakeLockWithoutContext() in WakeLockContextProvider mojo interface.
    
1) Add GetWakeLockWithoutContext in WakeLockContextProvider.
2) Rename WakeLockContextProvider to WakeLockProvider as it provides both
WakeLockService and WakeLockContext.
3) Convert download_request_core to be client of wakelock.

BUG=689410
TBR=jam@chromium.org, for mechanical changes in
//content/browser/wake_lock/wake_lock_context_host{.h|.cc}

Review-Url: https://codereview.chromium.org/2874013002
Cr-Commit-Position: refs/heads/master@{#471629}
Committed:
https://chromium.googlesource.com/chromium/src/+/2d8b867dfc360643d87634931521...
==========

[commit-bot: I haz the power, 2017-05-14 12:10:00]

Committed patchset #7 (id:120001) as
https://chromium.googlesource.com/chromium/src/+/2d8b867dfc360643d87634931521...