[sessions] Remove most knowledge of //chrome from core tab restore code

[sessions] Remove most knowledge of //chrome from core tab restore code

As part of the effort to componentize tab restore code, this CL removes most remaining knowledge of //chrome from that code, replacing it with abstraction through TabRestoreServiceClient:

- Profile::GetPath()
- Metrics for recording extensions apps launching
- Usage of //chrome-level URL constant

BUG=528883
Committed: https://crrev.com/a068d381e200d311d6fa7e387507924d06494b89
Cr-Commit-Position: refs/heads/master@{#348206}

[blundell, 2015-09-09 12:02:01]

blundell@chromium.org changed reviewers:
+ sky@chromium.org

[sky, 2015-09-09 15:57:59]

https://codereview.chromium.org/1309363007/diff/20001/chrome/browser/sessions...
File chrome/browser/sessions/chrome_tab_restore_service_client.h (right):

https://codereview.chromium.org/1309363007/diff/20001/chrome/browser/sessions...
chrome/browser/sessions/chrome_tab_restore_service_client.h:27: void
OnTabRestored(const GURL& url) override;
Is it possible to have the call sites do this book keeping?

[blundell, 2015-09-09 16:03:13]

https://codereview.chromium.org/1309363007/diff/20001/chrome/browser/sessions...
File chrome/browser/sessions/chrome_tab_restore_service_client.h (right):

https://codereview.chromium.org/1309363007/diff/20001/chrome/browser/sessions...
chrome/browser/sessions/chrome_tab_restore_service_client.h:27: void
OnTabRestored(const GURL& url) override;
On 2015/09/09 15:57:59, sky wrote:
> Is it possible to have the call sites do this book keeping?

By "bookkeeping", are you referring to the body of RecordAppLaunch()? If so, the
reason that this isn't possible is because //components isn't allowed to depend
on //extensions.

[sky, 2015-09-09 19:52:05]

https://codereview.chromium.org/1309363007/diff/20001/chrome/browser/sessions...
File chrome/browser/sessions/chrome_tab_restore_service_client.h (right):

https://codereview.chromium.org/1309363007/diff/20001/chrome/browser/sessions...
chrome/browser/sessions/chrome_tab_restore_service_client.h:27: void
OnTabRestored(const GURL& url) override;
On 2015/09/09 16:03:13, blundell wrote:
> On 2015/09/09 15:57:59, sky wrote:
> > Is it possible to have the call sites do this book keeping?
> 
> By "bookkeeping", are you referring to the body of RecordAppLaunch()? If so,
the
> reason that this isn't possible is because //components isn't allowed to
depend
> on //extensions.

I was thinking more specifically if the places that call into the
TabRestoreService to initiate a restore could change to initiate the restore and
then log the metrics?

[blundell, 2015-09-10 12:23:25]

Patchset #3 (id:40001) has been deleted

[blundell, 2015-09-10 13:26:15]

On 2015/09/09 19:52:05, sky wrote:
>
https://codereview.chromium.org/1309363007/diff/20001/chrome/browser/sessions...
> File chrome/browser/sessions/chrome_tab_restore_service_client.h (right):
> 
>
https://codereview.chromium.org/1309363007/diff/20001/chrome/browser/sessions...
> chrome/browser/sessions/chrome_tab_restore_service_client.h:27: void
> OnTabRestored(const GURL& url) override;
> On 2015/09/09 16:03:13, blundell wrote:
> > On 2015/09/09 15:57:59, sky wrote:
> > > Is it possible to have the call sites do this book keeping?
> > 
> > By "bookkeeping", are you referring to the body of RecordAppLaunch()? If so,
> the
> > reason that this isn't possible is because //components isn't allowed to
> depend
> > on //extensions.
> 
> I was thinking more specifically if the places that call into the
> TabRestoreService to initiate a restore could change to initiate the restore
and
> then log the metrics?

I see, I had misunderstood.

This would be all callers to TabRestoreService::RestoreMostRecentEntry() and
TabRestoreService::RestoreEntryById(). In total, 
there are 9 callers of those two methods in production code in //chrome. In my 
mind, changing those 9 callsites + facing the chance that new //chrome-level 
callsites don't understand that they need to do the bookkeeping as well is a 
maintainability loss compared to keeping the bookkeeping internal to the tab 
restore feature. What do you think?

[sky, 2015-09-10 17:58:06]

Your logic sounds right. LGTM

[blundell, 2015-09-10 18:45:05]

The CQ bit was checked by blundell@chromium.org

[commit-bot: I haz the power, 2015-09-10 18:45:26]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1309363007/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1309363007/60001

[commit-bot: I haz the power, 2015-09-10 19:20:04]

Committed patchset #3 (id:60001)

[commit-bot: I haz the power, 2015-09-10 19:20:47]

Patchset 3 (id:??) landed as
https://crrev.com/a068d381e200d311d6fa7e387507924d06494b89
Cr-Commit-Position: refs/heads/master@{#348206}

[commit-bot: I haz the power, 2015-09-23 12:12:59]

Patchset 3 (id:??) landed as
https://crrev.com/a068d381e200d311d6fa7e387507924d06494b89
Cr-Commit-Position: refs/heads/master@{#348206}