Update Blink to use the tree scope info on WebFrame for scoping checks.

Source/core/page/FrameTree.cpp

Index: Source/core/page/FrameTree.cpp
diff --git a/Source/core/page/FrameTree.cpp b/Source/core/page/FrameTree.cpp
index 3c73ba1ff8529189d166609c663e38058ae67847..27677ce7cfd7db35886482923a4b133276633619 100644
--- a/Source/core/page/FrameTree.cpp
+++ b/Source/core/page/FrameTree.cpp
@@ -172,25 +172,12 @@ AtomicString FrameTree::uniqueChildName(const AtomicString& requestedName) const
 
 Frame* FrameTree::scopedChild(unsigned index) const
 {
-    // TODO(dcheng, alexmos): Currently, all children of a RemoteFrame are
-    // visible, even through a shadow DOM scope.  Once RemoteFrames have a
-    // TreeScope, it should be used here.
-    TreeScope* scope = nullptr;
-    if (m_thisFrame->isLocalFrame()) {
-        scope = toLocalFrame(m_thisFrame)->document();
-        if (!scope)
-            return nullptr;
-    }
-
     unsigned scopedIndex = 0;
-    for (Frame* result = firstChild(); result; result = result->tree().nextSibling()) {
-        // TODO(dcheng, alexmos): Currently, RemoteFrames are always visible,
-        // even through a shadow DOM scope. Once RemoteFrames have a TreeScope,
-        // the scoping check should apply to RemoteFrames too.
-        if (scope && result->isLocalFrame() && !toLocalFrame(result)->inScope(scope))
+    for (Frame* child = firstChild(); child; child = child->tree().nextSibling()) {
+        if (child->client()->inShadowTree())
             continue;
         if (scopedIndex == index)
-            return result;
+            return child;
         scopedIndex++;
     }
 
@@ -199,35 +186,20 @@ Frame* FrameTree::scopedChild(unsigned index) const
 
 Frame* FrameTree::scopedChild(const AtomicString& name) const
 {
-    // TODO(dcheng, alexmos): Currently, all children of a RemoteFrame are
-    // visible, even through a shadow DOM scope.  Once RemoteFrames have a
-    // TreeScope, it should be used here.
-    TreeScope* scope = nullptr;
-    if (m_thisFrame->isLocalFrame()) {
-        scope = toLocalFrame(m_thisFrame)->document();
-        if (!scope)
-            return nullptr;
-    }
-
-    for (Frame* child = firstChild(); child; child = child->tree().nextSibling())
-        // TODO(dcheng, alexmos): Currently, RemoteFrames are always visible,
-        // even through a shadow DOM scope. Once RemoteFrames have a TreeScope,
-        // the scoping check should apply to RemoteFrames too.
-        if (child->tree().name() == name && (!scope || !child->isLocalFrame() || toLocalFrame(child)->inScope(scope)))
+    for (Frame* child = firstChild(); child; child = child->tree().nextSibling()) {
+        if (child->client()->inShadowTree())
+            continue;
+        if (child->tree().name() == name)
             return child;
+    }
     return nullptr;
 }
 
 inline unsigned FrameTree::scopedChildCount(TreeScope* scope) const
 {
-    // TODO(dcheng, alexmos): Once RemoteFrames have a TreeScope, this should
-    // return 0 if there is no scope.
-
     unsigned scopedCount = 0;
-    for (Frame* result = firstChild(); result; result = result->tree().nextSibling()) {
-        // FIXME: Currently, RemoteFrames are always visible, even through a shadow DOM scope.
-        // Once RemoteFrames have a TreeScope, the scoping check should apply to RemoteFrames too.
-        if (scope && result->isLocalFrame() && !toLocalFrame(result)->inScope(scope))
+    for (Frame* child = firstChild(); child; child = child->tree().nextSibling()) {
+        if (child->client()->inShadowTree())
             continue;
         scopedCount++;
     }