[iOS] Add HistoryDatabaseParamsForPath in //components/history/ios/browser

[iOS] Add HistoryDatabaseParamsForPath in //components/history/ios/browser

Add new helper method to construct an HistoryDatabaseParams for a FilePath
on iOS. Constants used for DownloadInterruptReason are based on the values
from content/public/browser/download_interrupt_reasons.h.

BUG=370850
Committed: https://crrev.com/70d2cd67184a81c7c8207de3dc0a58a2dcee2a30
Cr-Commit-Position: refs/heads/master@{#326808}

[sdefresne, 2015-04-24 14:32:22]

sdefresne@chromium.org changed reviewers:
+ droger@chromium.org

[sdefresne, 2015-04-24 14:32:22]

PTAL

[droger, 2015-04-24 14:38:29]

https://codereview.chromium.org/1106763002/diff/1/components/history/ios/brow...
File components/history/ios/browser/history_database_helper.cc (right):

https://codereview.chromium.org/1106763002/diff/1/components/history/ios/brow...
components/history/ios/browser/history_database_helper.cc:16: // The download
was interrupted by a browser crash. Internal use only.
1) What does "Internal use only" means?

2) Why are these values 0 and 50? If this is important, please explain where
they come from, or at least a comment telling to not change them.

[sdefresne, 2015-04-24 14:44:59]

The CQ bit was checked by sdefresne@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-04-24 14:45:23]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1106763002/20001

[sdefresne, 2015-04-24 14:46:29]

On 2015/04/24 14:38:29, droger wrote:
>
https://codereview.chromium.org/1106763002/diff/1/components/history/ios/brow...
> File components/history/ios/browser/history_database_helper.cc (right):
> 
>
https://codereview.chromium.org/1106763002/diff/1/components/history/ios/brow...
> components/history/ios/browser/history_database_helper.cc:16: // The download
> was interrupted by a browser crash. Internal use only.
> 1) What does "Internal use only" means?

It means that only history code sets it (i.e. on startup, all download whose
DownloadState is not DownloadComplete have their interrupt reason set to this
one). Remove since this is not visible outside of this file.

> 2) Why are these values 0 and 50? If this is important, please explain where
> they come from, or at least a comment telling to not change them.

Added comment that they are copied from
content/public/browser/download_interrupt_reasons.h and they should be kept in
sync until the file is no longer used.

[droger, 2015-04-24 14:47:29]

lgtm

[commit-bot: I haz the power, 2015-04-24 15:48:44]

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

[commit-bot: I haz the power, 2015-04-24 15:48:44]

Dry run: This issue passed the CQ dry run.

[sdefresne, 2015-04-24 15:57:57]

The CQ bit was checked by sdefresne@chromium.org

[commit-bot: I haz the power, 2015-04-24 15:58:17]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1106763002/20001

[commit-bot: I haz the power, 2015-04-24 15:59:22]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-04-24 16:00:08]

Patchset 2 (id:??) landed as
https://crrev.com/70d2cd67184a81c7c8207de3dc0a58a2dcee2a30
Cr-Commit-Position: refs/heads/master@{#326808}