DevTools: [Elements] Restore selected shadow DOM elements on reload

Source/core/inspector/InspectorDOMAgent.cpp

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Google Inc. All rights reserved.
  * Copyright (C) 2009 Joseph Pecoraro
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
@@ skipping 1983 matching lines @@
     // If a PseudoElement is bound, its parent element must be bound, too.
     Element* parent = pseudoElement->parentOrShadowHostElement();
     ASSERT(parent);
     int parentId = m_documentNodeToIdMap.get(parent);
     ASSERT(parentId);
 
     unbind(pseudoElement, &m_documentNodeToIdMap);
     m_frontend->pseudoElementRemoved(parentId, pseudoElementId);
 }
 
+static ShadowRoot* shadowRootForNode(Node* node, const String& type)
+{
+    if (!node->isElementNode())
+        return 0;
+    if (type == "a")
+        return toElement(node)->shadowRoot();
+    if (type == "u")
+        return toElement(node)->userAgentShadowRoot();
+    return 0;
+}
+
 Node* InspectorDOMAgent::nodeForPath(const String& path)
 {
-    // The path is of form "1,HTML,2,BODY,1,DIV"
+    // The path is of form "1,HTML,2,BODY,1,DIV" (<index> and <nodeName> interleaved).
+    // <index> may also be "a" (author shadow root) or "u" (user-agent shadow root),
+    // in which case <nodeName> MUST be "#document-fragment".
     if (!m_document)
         return 0;
 
     Node* node = m_document.get();
     Vector<String> pathTokens;
     path.split(",", false, pathTokens);
     if (!pathTokens.size())
         return 0;
     for (size_t i = 0; i < pathTokens.size() - 1; i += 2) {
         bool success = true;
-        unsigned childNumber = pathTokens[i].toUInt(&success);
-        if (!success)
-            return 0;
-        if (childNumber >= innerChildNodeCount(node))
-            return 0;
+        String& indexValue = pathTokens[i];
+        unsigned childNumber = indexValue.toUInt(&success);
+        Node* child;
+        if (!success) {
+            child = shadowRootForNode(node, indexValue);
+        } else {
+            if (childNumber >= innerChildNodeCount(node))
+                return 0;
 
-        Node* child = innerFirstChild(node);
+            child = innerFirstChild(node);
+        }
         String childName = pathTokens[i + 1];
         for (size_t j = 0; child && j < childNumber; ++j)
             child = innerNextSibling(child);
 
         if (!child || child->nodeName() != childName)
             return 0;
         node = child;
     }
     return node;
 }
@@ skipping 63 matching lines @@
     if (!m_documentNodeToIdMap.contains(m_document)) {
         RefPtr<TypeBuilder::DOM::Node> root;
         getDocument(errorString, root);
         return errorString->isEmpty();
     }
     return true;
 }
 
 } // namespace WebCore