DevTools: matched styles respect :visited/:link pseudo classes

DevTools: matched styles respect :visited/:link pseudo classes

Method StyleResolver::pseudoCSSRulesForElement is used from both WebPlatform
(via window.getMatchedCSSRules) and inspector in its styles sidebar pane.
Due to security reasons, this method "lies" about css rules applied for
visited and unvisited links so that it is impossible to sniff user history.

This patch makes inspector to adjust method results so that it knows which
rules are actually applied and which are not.

FYI: The previous version of this patch is https://codereview.chromium.org/228673002/
It was reverted due to regression of :host rules, thus this patch adds
a test to verify them.

BUG=356999
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=174963

[lushnikov, 2014-05-26 13:59:04]

please take a look

[apavlov, 2014-05-26 14:03:40]

lgtm with nits

"this test adds" -> "this patch adds" in the description

https://codereview.chromium.org/300693004/diff/1/Source/core/inspector/Inspec...
File Source/core/inspector/InspectorCSSAgent.cpp (right):

https://codereview.chromium.org/300693004/diff/1/Source/core/inspector/Inspec...
Source/core/inspector/InspectorCSSAgent.cpp:1294: if (element->isLink()) {
Early bailout:

if (!element->isLink())
    return linkState;

[lushnikov, 2014-05-26 15:06:13]

The CQ bit was checked by lushnikov@chromium.org

[lushnikov, 2014-05-26 15:06:22]

Thanks!

[commit-bot: I haz the power, 2014-05-26 15:06:39]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/lushnikov@chromium.org/300693004/20001

[commit-bot: I haz the power, 2014-05-26 16:32:19]

FYI, CQ is re-trying this CL (attempt #1).
Please consider checking whether the failures are real,
and report flakes to chrome-troopers@google.com.
The failing builders are:
  linux_blink_dbg on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/linux_blink_dbg/builds/9715)
  linux_blink_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/linux_blink_rel/builds/9534)
  mac_blink_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/mac_blink_rel/builds/8989)
  win_blink_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/win_blink_rel/builds/9171)

[lushnikov, 2014-05-26 16:53:23]

The CQ bit was unchecked by lushnikov@chromium.org

[lushnikov, 2014-05-27 17:07:30]

@apavlov, please take another look - previous patch was incorrect =/

[apavlov, 2014-05-28 09:17:09]

lgtm with comments

https://codereview.chromium.org/300693004/diff/40001/Source/core/inspector/In...
File Source/core/inspector/InspectorCSSAgent.cpp (right):

https://codereview.chromium.org/300693004/diff/40001/Source/core/inspector/In...
Source/core/inspector/InspectorCSSAgent.cpp:1287:
SelectorChecker::SelectorCheckingContext shadowDomContext(selector, &element,
SelectorChecker::VisitedMatchEnabled);
shadowDOMContext, to follow the guidelines

https://codereview.chromium.org/300693004/diff/40001/Source/core/inspector/In...
Source/core/inspector/InspectorCSSAgent.cpp:1291: return
selectorChecker.match(selectorCheckingContext, DOMSiblingTraversalStrategy()) ==
SelectorChecker::SelectorMatches
Please split this into two distinct operations to avoid the unnecessary
shadowDOMContext creation

[lushnikov, 2014-05-28 10:59:02]

Great, thanks!

https://codereview.chromium.org/300693004/diff/40001/Source/core/inspector/In...
File Source/core/inspector/InspectorCSSAgent.cpp (right):

https://codereview.chromium.org/300693004/diff/40001/Source/core/inspector/In...
Source/core/inspector/InspectorCSSAgent.cpp:1287:
SelectorChecker::SelectorCheckingContext shadowDomContext(selector, &element,
SelectorChecker::VisitedMatchEnabled);
On 2014/05/28 09:17:09, apavlov wrote:
> shadowDOMContext, to follow the guidelines

Done.

https://codereview.chromium.org/300693004/diff/40001/Source/core/inspector/In...
Source/core/inspector/InspectorCSSAgent.cpp:1291: return
selectorChecker.match(selectorCheckingContext, DOMSiblingTraversalStrategy()) ==
SelectorChecker::SelectorMatches
On 2014/05/28 09:17:09, apavlov wrote:
> Please split this into two distinct operations to avoid the unnecessary
> shadowDOMContext creation

Done.

[lushnikov, 2014-05-28 10:59:06]

The CQ bit was checked by lushnikov@chromium.org

[commit-bot: I haz the power, 2014-05-28 10:59:30]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/lushnikov@chromium.org/300693004/50001

[commit-bot: I haz the power, 2014-05-28 12:14:37]

Change committed as 174963