Improve consistency of nextNodeWithGreaterTabIndex() and previousNodeWithLowerTabIndex().

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 e595789d202ce61f9f4ef7f69d2e7948a475038a..66193025cad35f744650a3d89b1904dda999f677 100644
--- a/Source/core/page/FocusController.cpp
+++ b/Source/core/page/FocusController.cpp
@@ -549,7 +549,7 @@ static Node* nextNodeWithGreaterTabIndex(Node* start, int tabIndex)
         int currentTabIndex = adjustedTabIndex(&node);
         if (shouldVisit(&node) && currentTabIndex > tabIndex && currentTabIndex < winningTabIndex) {
             winner = &node;
-            winningTabIndex = node.tabIndex();
+            winningTabIndex = currentTabIndex;
         }
     }
 
@@ -563,7 +563,7 @@ static Node* previousNodeWithLowerTabIndex(Node* start, int tabIndex)
     Node* winner = nullptr;
     for (Node* node = start; node; node = NodeTraversal::previous(*node)) {
         int currentTabIndex = adjustedTabIndex(node);
-        if ((shouldVisit(node) || isNonKeyboardFocusableShadowHost(node)) && currentTabIndex < tabIndex && currentTabIndex > winningTabIndex) {
+        if (shouldVisit(node) && currentTabIndex < tabIndex && currentTabIndex > winningTabIndex) {
             winner = node;
             winningTabIndex = currentTabIndex;
         }