Get rid of DownloadItemImpl::UpdateProgress()

Get rid of DownloadItemImpl::UpdateProgress()

Changed SavePackage and unit tests to use DestinationUpdated(). This
function does the same work as UpdateProgress(). We stick to
DestinationUpdated() since it's part of DownloadDestinationObserver
interface (so already used elsewhere).

This patch makes the interface implementation as public to allow
access from SavePackage and unit tests. These functions were already
public in the interface itself.

BUG=239475
TEST=content_unittests and making sure chrome is built

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=200301

[asanka, 2013-05-13 20:35:55]

cmarcelo: Did you sign the CLA or the CCLA? The CLA can be found at
https://developers.google.com/open-source/cla/individual.

The patch itself LGTM.

Could you add a 'Patch from Your Name <email@example.com>' line to the CL
description?

[cmarcelo, 2013-05-14 19:27:26]

Rebased and added the "Patch from". I'm already covered by the CLA signed by the
company I work for.

[commit-bot: I haz the power, 2013-05-14 19:52:00]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/caio.de.oliveira.filho@intel.com/14646...

[commit-bot: I haz the power, 2013-05-14 21:34:27]

Retried try job too often on win_rel for step(s) unit_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2013-05-15 14:25:22]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/caio.de.oliveira.filho@intel.com/14646...

[commit-bot: I haz the power, 2013-05-15 17:00:05]

Change committed as 200301