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diff --git a/chromium/third_party/blink/renderer/core/page/scrolling/fragment_anchor.h b/chromium/third_party/blink/renderer/core/page/scrolling/fragment_anchor.h
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+++ b/chromium/third_party/blink/renderer/core/page/scrolling/fragment_anchor.h
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+// Copyright 2019 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 THIRD_PARTY_BLINK_RENDERER_CORE_PAGE_SCROLLING_FRAGMENT_ANCHOR_H_
+#define THIRD_PARTY_BLINK_RENDERER_CORE_PAGE_SCROLLING_FRAGMENT_ANCHOR_H_
+
+#include "third_party/blink/renderer/core/core_export.h"
+#include "third_party/blink/renderer/platform/heap/handle.h"
+#include "third_party/blink/renderer/platform/scroll/scroll_types.h"
+
+namespace blink {
+
+class LocalFrame;
+class KURL;
+
+// This class encapsulates the behavior of a "fragment anchor". A fragment
+// anchor allows a page to link to a specific part of a page by specifying an
+// element id in the URL fragment. The fragment is the part after the '#'
+// character. E.g. navigating to www.example.com/index.html#section3 will find
+// the element with id "section3" and focus and scroll it into view.
+//
+// While the page is loading, the fragment anchor tries to repeatedly scroll
+// the element into view since it's position may change as a result of layouts.
+// TODO(bokan): Maybe we no longer need the repeated scrolling since that
+// should be handled by scroll-anchoring?
+class CORE_EXPORT FragmentAnchor : public GarbageCollected<FragmentAnchor> {
+ public:
+  // Parses the fragment string and tries to create a FragmentAnchor object. If
+  // an appropriate target was found based on the given fragment, this method
+  // will create and return a FragmentAnchor object that can be used to keep it
+  // in view.  Otherwise, this will return nullptr. In either case,
+  // side-effects on the document will be performed, for example,
+  // setting/clearing :target and svgView(). If needs_invoke is false, only the
+  // side effects will be performed, the element won't be scrolled/focused and
+  // this method returns nullptr (e.g. used during history navigation where we
+  // don't want to clobber the history scroll restoration).
+  static FragmentAnchor* TryCreate(const KURL& url,
+                                   bool needs_invoke,
+                                   LocalFrame& frame);
+
+  FragmentAnchor(Node& anchor_node, LocalFrame& frame);
+  virtual ~FragmentAnchor() = default;
+
+  // Invoking the fragment anchor scrolls it into view and performs any other
+  // desired actions. This is called repeatedly during loading as the lifecycle
+  // is updated to keep the element in view. If true, the anchor should be kept
+  // alive and invoked again. Otherwise it may be disposed.
+  bool Invoke();
+
+  // Used to let the fragment know the frame's been scrolled and so we should
+  // abort keeping the fragment target in view to avoid fighting with user
+  // scrolls.
+  void DidScroll(ScrollType type);
+
+  void PerformPreRafActions();
+
+  void DidCompleteLoad();
+
+  void Trace(blink::Visitor*);
+
+ private:
+  void ApplyFocusIfNeeded();
+
+  WeakMember<Node> anchor_node_;
+  Member<LocalFrame> frame_;
+  bool needs_focus_;
+
+  // While this is true, the fragment is still "active" in the sense that we
+  // want the owner to continue calling Invoke(). Once this is false, calling
+  // Invoke has no effect and the fragment can be disposed.
+  bool needs_invoke_ = true;
+};
+
+}  // namespace blink
+
+#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_PAGE_SCROLLING_FRAGMENT_ANCHOR_H_