Use main frame URL to identify referrer if sub-frame url is not available

In identifying download referrer chain, if the subframe url is not
available (e.g. empty), we should use main frame url to search for
previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.
For example, page A has a link to page B, and page B has a
subframe C, and subframe C links to download D.

A --->  B
        \iframe C -----> D
If we only look at the frame D's in, we can only reach C in
attribution. But in fact it should be D-C-B-A.

BUG=639467
Committed: https://crrev.com/f5e07b74bfbc8bf109bdf9855b0a6c0214085d73
Cr-Commit-Position: refs/heads/master@{#441454}

[Jialiu Lin, 2017-01-04 00:41:46]

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

[commit-bot: I haz the power, 2017-01-04 00:42:13]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Jialiu Lin, 2017-01-04 00:46:23]

Description was changed from

==========
When trace back navigation events, if the subframe url is not available,
we should use main frame url to search for previous navigation.

BUG=639467
==========

to

==========
In identifying download referrer chain, if the subframe url is not available
(e.g. empty), we should use main frame url to search for previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.

BUG=639467
==========

[Jialiu Lin, 2017-01-04 00:51:55]

Description was changed from

==========
In identifying download referrer chain, if the subframe url is not available
(e.g. empty), we should use main frame url to search for previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.

BUG=639467
==========

to

==========
In identifying download referrer chain, if the subframe url is not 
available (e.g. empty), we should use main frame url to search for 
previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.
For example, page A has a link to page B, and page B has a subframe C, and
subframe C links to download D. 
A --->  B  
        -iframe C -----> D
If we only look at the frame D's in, we can only reach C in attribution. But in
fact it should be D-C-B-A. 

BUG=639467
==========

[Jialiu Lin, 2017-01-04 00:52:26]

Description was changed from

==========
In identifying download referrer chain, if the subframe url is not 
available (e.g. empty), we should use main frame url to search for 
previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.
For example, page A has a link to page B, and page B has a subframe C, and
subframe C links to download D. 
A --->  B  
        -iframe C -----> D
If we only look at the frame D's in, we can only reach C in attribution. But in
fact it should be D-C-B-A. 

BUG=639467
==========

to

==========
In identifying download referrer chain, if the subframe url is not 
available (e.g. empty), we should use main frame url to search for 
previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.
For example, page A has a link to page B, and page B has a 
subframe C, and subframe C links to download D. 

A --->  B  
        -iframe C -----> D
If we only look at the frame D's in, we can only reach C in
attribution. But in fact it should be D-C-B-A. 

BUG=639467
==========

[Jialiu Lin, 2017-01-04 01:12:02]

Description was changed from

==========
In identifying download referrer chain, if the subframe url is not 
available (e.g. empty), we should use main frame url to search for 
previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.
For example, page A has a link to page B, and page B has a 
subframe C, and subframe C links to download D. 

A --->  B  
        -iframe C -----> D
If we only look at the frame D's in, we can only reach C in
attribution. But in fact it should be D-C-B-A. 

BUG=639467
==========

to

==========
In identifying download referrer chain, if the subframe url is not 
available (e.g. empty), we should use main frame url to search for 
previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.
For example, page A has a link to page B, and page B has a 
subframe C, and subframe C links to download D. 

A --->  B  
        \iframe C -----> D
If we only look at the frame D's in, we can only reach C in
attribution. But in fact it should be D-C-B-A. 

BUG=639467
==========

[commit-bot: I haz the power, 2017-01-04 01:51:57]

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

[commit-bot: I haz the power, 2017-01-04 01:51:59]

Dry run: This issue passed the CQ dry run.

[Jialiu Lin, 2017-01-04 01:53:44]

jialiul@chromium.org changed reviewers:
+ nparker@chromium.org

[Jialiu Lin, 2017-01-04 01:53:45]

Hi nparker@,
PTAL. Thanks!

[Nathan Parker, 2017-01-04 18:54:51]

lgtm

https://codereview.chromium.org/2612663002/diff/1/chrome/browser/safe_browsin...
File chrome/browser/safe_browsing/safe_browsing_navigation_observer_manager.cc
(right):

https://codereview.chromium.org/2612663002/diff/1/chrome/browser/safe_browsin...
chrome/browser/safe_browsing/safe_browsing_navigation_observer_manager.cc:361:
GURL search_url = target_url.is_empty() ? target_main_frame_url : target_url;
nit: could be 
const GURL&
so you don't make a copy.

https://codereview.chromium.org/2612663002/diff/1/chrome/browser/safe_browsin...
File chrome/browser/safe_browsing/safe_browsing_navigation_observer_manager.h
(right):

https://codereview.chromium.org/2612663002/diff/1/chrome/browser/safe_browsin...
chrome/browser/safe_browsing/safe_browsing_navigation_observer_manager.h:159:
const GURL& target_main_frame_url,
Mention this new arg in the comments

[Jialiu Lin, 2017-01-04 19:33:36]

The CQ bit was checked by jialiul@chromium.org

[Jialiu Lin, 2017-01-04 19:33:37]

The patchset sent to the CQ was uploaded after l-g-t-m from nparker@chromium.org
Link to the patchset: https://codereview.chromium.org/2612663002/#ps20001
(title: "address comments from nparker@")

[commit-bot: I haz the power, 2017-01-04 19:34:07]

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, 2017-01-04 20:37:39]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1483558416572290,
"parent_rev": "c49337ef00a1d17140c957da579796bd852a6389", "commit_rev":
"153bba1b8d33c6cb02933913a33011722ff12535"}

[commit-bot: I haz the power, 2017-01-04 20:38:07]

Description was changed from

==========
In identifying download referrer chain, if the subframe url is not 
available (e.g. empty), we should use main frame url to search for 
previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.
For example, page A has a link to page B, and page B has a 
subframe C, and subframe C links to download D. 

A --->  B  
        \iframe C -----> D
If we only look at the frame D's in, we can only reach C in
attribution. But in fact it should be D-C-B-A. 

BUG=639467
==========

to

==========
In identifying download referrer chain, if the subframe url is not 
available (e.g. empty), we should use main frame url to search for 
previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.
For example, page A has a link to page B, and page B has a 
subframe C, and subframe C links to download D. 

A --->  B  
        \iframe C -----> D
If we only look at the frame D's in, we can only reach C in
attribution. But in fact it should be D-C-B-A. 

BUG=639467

Review-Url: https://codereview.chromium.org/2612663002
==========

[commit-bot: I haz the power, 2017-01-04 20:38:08]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2017-01-04 20:40:28]

Description was changed from

==========
In identifying download referrer chain, if the subframe url is not 
available (e.g. empty), we should use main frame url to search for 
previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.
For example, page A has a link to page B, and page B has a 
subframe C, and subframe C links to download D. 

A --->  B  
        \iframe C -----> D
If we only look at the frame D's in, we can only reach C in
attribution. But in fact it should be D-C-B-A. 

BUG=639467

Review-Url: https://codereview.chromium.org/2612663002
==========

to

==========
In identifying download referrer chain, if the subframe url is not
available (e.g. empty), we should use main frame url to search for
previous navigation.

This will help us correctly identify referrer of downloads that
happen in sub-frame.
For example, page A has a link to page B, and page B has a
subframe C, and subframe C links to download D.

A --->  B
        \iframe C -----> D
If we only look at the frame D's in, we can only reach C in
attribution. But in fact it should be D-C-B-A.

BUG=639467

Committed: https://crrev.com/f5e07b74bfbc8bf109bdf9855b0a6c0214085d73
Cr-Commit-Position: refs/heads/master@{#441454}
==========

[commit-bot: I haz the power, 2017-01-04 20:40:29]

Patchset 2 (id:??) landed as
https://crrev.com/f5e07b74bfbc8bf109bdf9855b0a6c0214085d73
Cr-Commit-Position: refs/heads/master@{#441454}

[Jialiu Lin, 2017-01-04 21:47:01]

https://codereview.chromium.org/2612663002/diff/1/chrome/browser/safe_browsin...
File chrome/browser/safe_browsing/safe_browsing_navigation_observer_manager.cc
(right):

https://codereview.chromium.org/2612663002/diff/1/chrome/browser/safe_browsin...
chrome/browser/safe_browsing/safe_browsing_navigation_observer_manager.cc:361:
GURL search_url = target_url.is_empty() ? target_main_frame_url : target_url;
On 2017/01/04 18:54:51, Nathan Parker wrote:
> nit: could be 
> const GURL&
> so you don't make a copy.

Done.

https://codereview.chromium.org/2612663002/diff/1/chrome/browser/safe_browsin...
File chrome/browser/safe_browsing/safe_browsing_navigation_observer_manager.h
(right):

https://codereview.chromium.org/2612663002/diff/1/chrome/browser/safe_browsin...
chrome/browser/safe_browsing/safe_browsing_navigation_observer_manager.h:159:
const GURL& target_main_frame_url,
On 2017/01/04 18:54:51, Nathan Parker wrote:
> Mention this new arg in the comments

Done.