Remove tabStop feature

Source/core/page/FocusController.cpp

Index: Source/core/page/FocusController.cpp
diff --git a/Source/core/page/FocusController.cpp b/Source/core/page/FocusController.cpp
index 26309721f2fddf73e07a39f4e007ac4825fba1fa..ee452bc96cf9711f6a014bca6874239d80ae2ccc 100644
--- a/Source/core/page/FocusController.cpp
+++ b/Source/core/page/FocusController.cpp
@@ -526,7 +526,7 @@ Node* FocusController::findFocusableNodeAcrossFocusScopesBackward(const FocusNav
         if (!owner)
             break;
         currentScope = FocusNavigationScope::focusNavigationScopeOf(*owner);
-        if (isKeyboardFocusableShadowHost(*owner) && toElement(owner)->tabStop()) {
+        if (isKeyboardFocusableShadowHost(*owner)) {
             found = owner;
             break;
         }
@@ -548,16 +548,6 @@ Node* FocusController::findFocusableNodeRecursivelyForward(const FocusNavigation
     Node* found = findFocusableNode(WebFocusTypeForward, scope, start);
     if (!found)
         return nullptr;
-    if (found->isElementNode() && !toElement(found)->tabStop()) {
-        if (isShadowHostWithoutCustomFocusLogic(*found)) {
-            FocusNavigationScope innerScope = FocusNavigationScope::ownedByShadowHost(*found);
-            Node* foundInInnerFocusScope = findFocusableNodeRecursivelyForward(innerScope, nullptr);
-            return foundInInnerFocusScope ? foundInInnerFocusScope : findFocusableNodeRecursivelyForward(scope, found);
-        }
-        // Skip to the next node.
-        if (!isNonFocusableFocusScopeOwner(*found))
-            found = findFocusableNodeRecursivelyForward(scope, found);
-    }
     if (!found || !isNonFocusableFocusScopeOwner(*found))
         return found;
 
@@ -584,8 +574,6 @@ Node* FocusController::findFocusableNodeRecursivelyBackward(const FocusNavigatio
         Node* foundInInnerFocusScope = findFocusableNodeRecursivelyBackward(innerScope, nullptr);
         if (foundInInnerFocusScope)
             return foundInInnerFocusScope;
-        if (found->isElementNode() && !toElement(found)->tabStop())
-            found = findFocusableNodeRecursivelyBackward(scope, found);
         return found;
     }
 
@@ -598,7 +586,7 @@ Node* FocusController::findFocusableNodeRecursivelyBackward(const FocusNavigatio
         return foundInInnerFocusScope ? foundInInnerFocusScope : findFocusableNodeRecursivelyBackward(scope, found);
     }
 
-    return found->isElementNode() && toElement(found)->tabStop() ? found : findFocusableNodeRecursivelyBackward(scope, found);
+    return found;
 }
 
 static Node* findNodeWithExactTabIndex(Node* start, int tabIndex, WebFocusType type)