Adds a FlatDomTreeExtractor to headless

headless/public/util/flat_dom_tree_extractor.h

-// Copyright 2016 The Chromium Authors. All rights reserved.
+// Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef HEADLESS_PUBLIC_UTIL_DOM_TREE_EXTRACTOR_H_
 #define HEADLESS_PUBLIC_UTIL_DOM_TREE_EXTRACTOR_H_
 
 #include <unordered_map>
 #include <vector>
 
 #include "base/macros.h"
 #include "headless/public/devtools/domains/css.h"
 #include "headless/public/devtools/domains/dom.h"
 
 namespace headless {
 class HeadlessDevToolsClient;
 
 // A utility class for extracting information from the DOM via DevTools. In
 // addition, it also extracts details of bounding boxes and layout text (NB the
 // exact layout should not be regarded as stable, it's subject to change without
 // notice).
-class DomTreeExtractor {
+class FlatDomTreeExtractor {
  public:
-  explicit DomTreeExtractor(HeadlessDevToolsClient* devtools_client);
-  ~DomTreeExtractor();
+  explicit FlatDomTreeExtractor(HeadlessDevToolsClient* devtools_client);
+  ~FlatDomTreeExtractor();
 
   using NodeId = int;
   using Index = size_t;
 
   class DomTree {
    public:
     DomTree();
     DomTree(DomTree&& other);
     ~DomTree();
 
     // Flattened dom tree. The root node is always the first entry.
     std::vector<const dom::Node*> dom_nodes_;
 
     // Map of node IDs to indexes into |dom_nodes_|.
     std::unordered_map<NodeId, Index> node_id_to_index_;
 
     std::vector<const css::LayoutTreeNode*> layout_tree_nodes_;
 
     std::vector<const css::ComputedStyle*> computed_styles_;
 
    private:
-    friend class DomTreeExtractor;
+    friend class FlatDomTreeExtractor;
 
     // Owns the raw pointers in |dom_nodes_|.
-    std::unique_ptr<dom::GetDocumentResult> document_result_;
+    std::unique_ptr<dom::GetFlattenedDocumentResult> document_result_;
 
     // Owns the raw pointers in |layout_tree_nodes_|.
     std::unique_ptr<css::GetLayoutTreeAndStylesResult>
         layout_tree_and_styles_result_;
 
     DISALLOW_COPY_AND_ASSIGN(DomTree);
   };
 
   using DomResultCB = base::Callback<void(DomTree)>;
 
   // Extracts all nodes from the DOM.  This is an asynchronous operation and
   // it's an error to call ExtractDom while a previous operation is in flight.
   void ExtractDomTree(const std::vector<std::string>& css_style_whitelist,
                       DomResultCB callback);
 
  private:
-  void OnDocumentFetched(std::unique_ptr<dom::GetDocumentResult> result);
+  void OnDocumentFetched(
+      std::unique_ptr<dom::GetFlattenedDocumentResult> result);
 
   void OnLayoutTreeAndStylesFetched(
       std::unique_ptr<css::GetLayoutTreeAndStylesResult> result);
 
   void MaybeExtractDomTree();
   void EnumerateNodes(const dom::Node* node);
   void ExtractLayoutTreeNodes();
   void ExtractComputedStyles();
 
   DomResultCB callback_;
   DomTree dom_tree_;
   bool work_in_progress_;
   HeadlessDevToolsClient* devtools_client_;  // NOT OWNED
-  base::WeakPtrFactory<DomTreeExtractor> weak_factory_;
+  base::WeakPtrFactory<FlatDomTreeExtractor> weak_factory_;
 
-  DISALLOW_COPY_AND_ASSIGN(DomTreeExtractor);
+  DISALLOW_COPY_AND_ASSIGN(FlatDomTreeExtractor);
 };
 
 }  // namespace headless
 
 #endif  // HEADLESS_PUBLIC_UTIL_DOM_TREE_EXTRACTOR_H_