third_party/WebKit/Source/web/ViewportAnchor.h

/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 *
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 * notice, this list of conditions and the following disclaimer.
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 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
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 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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#ifndef ViewportAnchor_h
#define ViewportAnchor_h

#include "platform/heap/Handle.h"

namespace blink {

class FrameView;
class VisualViewport;

// Use derived ViewportAnchor classes to "anchor" the viewport to a location,
// perform some operation that may move the viewport around, then restore
// the viewport to the original location.
// We support two kinds of anchors, a rotation anchor and a resize anchor.
class ViewportAnchor {
    STACK_ALLOCATED();
protected:
    ViewportAnchor(FrameView& rootFrameView, VisualViewport& visualViewport)
        : m_rootFrameView(&rootFrameView)
        , m_visualViewport(&visualViewport)
    {
    }

    RawPtrWillBeMember<FrameView> m_rootFrameView;
    RawPtrWillBeMember<VisualViewport> m_visualViewport;
};

} // namespace blink

#endif // ViewportAnchor_h