SelectorChecker::parentElement should walk up to ShadowHost only if an element is in a shadow tree …

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

Index: LayoutTests/fast/dom/shadow/style-with-cat.html
diff --git a/LayoutTests/fast/dom/shadow/style-with-cat.html b/LayoutTests/fast/dom/shadow/style-with-cat.html
index 2784d4020e17538b1946fa37d9f2d155e35e773b..6fcd5a9487abeedcd60ab3211bbf287dfe1513e8 100644
--- a/LayoutTests/fast/dom/shadow/style-with-cat.html
+++ b/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>