Track download request time and always send back the hash.

Track how long a typical SafeBrowsing download protection request takes.
This histogram will also tell us how often the server response got back
too late and the timeout was reached.

This CL also makes sure we always send back the file hash if the
enhanced download protection is enabled.

BUG=NONE
TEST=Run all unit-tests under DownloadProtectionServiceTest.

[Randy Smith (Not in Mondays), 2011-11-18 23:27:16]

http://codereview.chromium.org/8600006/diff/2001/chrome/browser/download/chro...
File chrome/browser/download/chrome_download_manager_delegate.cc (right):

http://codereview.chromium.org/8600006/diff/2001/chrome/browser/download/chro...
chrome/browser/download/chrome_download_manager_delegate.cc:214:
sb_service->download_protection_service()->enabled()));
Why this change?  Why can't sb_service->DownloadBinHashNeeded() include this
logic?

[noelutz, 2011-11-18 23:30:23]

http://codereview.chromium.org/8600006/diff/2001/chrome/browser/download/chro...
File chrome/browser/download/chrome_download_manager_delegate.cc (right):

http://codereview.chromium.org/8600006/diff/2001/chrome/browser/download/chro...
chrome/browser/download/chrome_download_manager_delegate.cc:214:
sb_service->download_protection_service()->enabled()));
On 2011/11/18 23:27:17, rdsmith wrote:
> Why this change?  Why can't sb_service->DownloadBinHashNeeded() include this
> logic?

Good point. Done.

[Brian Ryner, 2011-11-19 00:03:02]

lgtm

[commit-bot: I haz the power, 2011-11-19 00:39:15]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/noelutz@google.com/8600006/7003

[commit-bot: I haz the power, 2011-11-19 00:59:46]

Try job failure for 8600006-7003 (retry) on win_rel for step "compile" (clobber
build).
It's a second try, previously, step "compile" failed.
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...