SelectorChecker::parentElement should walk up to ShadowHost only if an element...

SelectorChecker::parentElement should walk up to ShadowHost only if an element is in a shadow tree hosted by the ShadowHost and scope is the ShadowHost.

:host can only match shadow host. :host depends on context.scope with ScopeIsShadowHost behavior.
So only if context.scope is shadow host and context.element's shadow host is context.scope, we need to check the shadow host.

BUG=370303
TEST=fast/dom/shadow/style-with-cat.html, fast/dom/shadow/style-with-hat.html

Review URL: https://codereview.chromium.org/273523008

git-svn-id: svn://svn.chromium.org/blink/trunk@173703 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/LayoutTests/fast/dom/shadow/style-with-cat-expected.txt

@@ -26,6 +26,8 @@ PASS borderColorOf(getNodeInTreeOfTrees("host//host2/target")) is "rgb(0, 128, 0
 PASS borderColorOf(getNodeInTreeOfTrees("child")) is not "rgb(255, 0, 0)"
 PASS borderColorOf(getNodeInTreeOfTrees("inner/target")) is not "rgb(255, 0, 0)"
 PASS borderColorOf(getNodeInTreeOfTrees("host//target")) is "rgb(0, 128, 0)"
+PASS borderColorOf(getNodeInTreeOfTrees("host/x-bar-host/x-bar-target")) is not "rgb(255, 0, 0)"
+PASS borderColorOf(getNodeInTreeOfTrees("host/x-bar-host/x-zot-host/x-zot-target")) is not "rgb(255, 0, 0)"
 PASS successfullyParsed is true
 
 TEST COMPLETE

third_party/WebKit/LayoutTests/fast/dom/shadow/style-with-cat.html

@@ -399,6 +399,27 @@ borderColorShouldBe('host//target', 'rgb(0, 128, 0)');
 
 cleanUp();
 
+sandbox.appendChild(
+    createDOM('div', {'id': 'host'},
+        createShadowRoot(
+            createDOM('style', {},
+                document.createTextNode('* /deep/ .x-bar div { border: 1px solid red; }')),
+            createDOM('div', {'id': 'x-foo'},
+                document.createTextNode('x-foo')),
+            createDOM('div', {},
+                createDOM('div', {'id': 'x-bar-host', 'class': 'x-bar'},
+                    createShadowRoot(
+                        createDOM('div', {'id': 'x-bar-target'},
+                            document.createTextNode('x-bar')),
+                        createDOM('div', {'id': 'x-zot-host', 'class': 'x-zot'},
+                            createShadowRoot(
+                                createDOM('div', {'id': 'x-zot-target'},
+                                    document.createTextNode('x-zot'))))))))));
+
+borderColorShouldNotBe('host/x-bar-host/x-bar-target', 'rgb(255, 0, 0)');
+borderColorShouldNotBe('host/x-bar-host/x-zot-host/x-zot-target', 'rgb(255, 0, 0)');
+cleanUp();
+
 </script>
 </html>
 

third_party/WebKit/LayoutTests/fast/dom/shadow/style-with-hat-expected.txt

@@ -26,6 +26,7 @@ PASS borderColorOf(getNodeInTreeOfTrees("host/host2/target")) is "rgb(0, 0, 0)"
 PASS borderColorOf(getNodeInTreeOfTrees("host/host2/target")) is "rgb(0, 128, 0)"
 PASS borderColorOf(getNodeInTreeOfTrees("host/host2/target")) is "rgb(0, 0, 0)"
 PASS borderColorOf(getNodeInTreeOfTrees("host//host2/target")) is "rgb(0, 128, 0)"
+PASS borderColorOf(getNodeInTreeOfTrees("host/x-bar-host/x-zot-host/x-zot-target")) is not "rgb(255, 0, 0)"
 PASS successfullyParsed is true
 
 TEST COMPLETE

third_party/WebKit/LayoutTests/fast/dom/shadow/style-with-hat.html

@@ -324,6 +324,25 @@ borderColorShouldBe('host//host2/target', 'rgb(0, 128, 0)');
 
 cleanUp();
 
+sandbox.appendChild(
+    createDOM('div', {'id': 'host'},
+        createShadowRoot(
+            createDOM('style', {},
+                document.createTextNode('.x-bar .x-zot::shadow div { border: 1px solid red; }')),
+            createDOM('div', {'id': 'x-foo'},
+                document.createTextNode('x-foo')),
+            createDOM('div', {'id': 'x-bar-host', 'class': 'x-bar'},
+                createShadowRoot(
+                    createDOM('div', {'id': 'x-bar-target'},
+                        document.createTextNode('x-bar')),
+                    createDOM('div', {'id': 'x-zot-host', 'class': 'x-zot'},
+                        createShadowRoot(
+                            createDOM('div', {'id': 'x-zot-target'},
+                                document.createTextNode('x-zot')))))))));
+
+borderColorShouldNotBe('host/x-bar-host/x-zot-host/x-zot-target', 'rgb(255, 0, 0)');
+cleanUp();
+
 </script>
 </html>
 

third_party/WebKit/Source/core/css/SelectorChecker.cpp

@@ -84,7 +84,7 @@ Element* SelectorChecker::parentElement(const SelectorCheckingContext& context,
         return context.element->parentOrShadowHostElement();
 
     // If context.scope is a shadow host, we should walk up from a shadow root to its shadow host.
-    if (context.behaviorAtBoundary & SelectorChecker::ScopeIsShadowHost)
+    if ((context.behaviorAtBoundary & SelectorChecker::ScopeIsShadowHost) && context.scope == context.element->shadowHost())
         return context.element->parentOrShadowHostElement();
 
     if ((context.behaviorAtBoundary & SelectorChecker::BoundaryBehaviorMask) != SelectorChecker::StaysWithinTreeScope)