Prefer lengthOfContents over countChildren

Source/core/editing/DOMSelection.cpp

Index: Source/core/editing/DOMSelection.cpp
diff --git a/Source/core/editing/DOMSelection.cpp b/Source/core/editing/DOMSelection.cpp
index 6a8a63ea9014d7162c73f7c3fced15217a6cb5e4..99020f47a1a002ac2c15e50aef28a3ee97296b57 100644
--- a/Source/core/editing/DOMSelection.cpp
+++ b/Source/core/editing/DOMSelection.cpp
@@ -344,7 +344,7 @@ void DOMSelection::extend(Node* node, int offset, ExceptionState& exceptionState
         exceptionState.throwDOMException(IndexSizeError, String::number(offset) + " is not a valid offset.");
         return;
     }
-    if (static_cast<unsigned>(offset) > (node->offsetInCharacters() ? node->lengthOfContents() : node->countChildren())) {
+    if (static_cast<unsigned>(offset) > node->lengthOfContents()) {
         exceptionState.throwDOMException(IndexSizeError, String::number(offset) + " is larger than the given node's length.");
         return;
     }