Turn ViewportAnchors into stack allocated objects.

Source/web/ResizeViewportAnchor.cpp

 // Copyright 2015 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.
 
 #include "config.h"
 #include "web/ResizeViewportAnchor.h"
 
 #include "core/frame/FrameView.h"
 #include "core/frame/PinchViewport.h"
 #include "platform/geometry/DoublePoint.h"
 #include "platform/geometry/DoubleSize.h"
 #include "platform/geometry/FloatSize.h"
 
 namespace blink {
 
 ResizeViewportAnchor::ResizeViewportAnchor(FrameView& rootFrameView, PinchViewport& pinchViewport)
-    : ViewportAnchor(rootFrameView, pinchViewport) { }
-
-
-void ResizeViewportAnchor::setAnchor()
+    : ViewportAnchor(rootFrameView, pinchViewport)
+    , m_pinchViewportInDocument(m_pinchViewport->visibleRectInDocument().location())
 {
-    m_pinchViewportInDocument = m_pinchViewport.visibleRectInDocument().location();
 }
 
-void ResizeViewportAnchor::restoreToAnchor()
+ResizeViewportAnchor::~ResizeViewportAnchor()
 {
-    FloatSize delta = m_pinchViewportInDocument - m_pinchViewport.visibleRectInDocument().location();
+    FloatSize delta = m_pinchViewportInDocument - m_pinchViewport->visibleRectInDocument().location();
 
-    DoublePoint targetFrameViewPosition = m_rootFrameView.scrollPositionDouble() + DoubleSize(delta);
-    m_rootFrameView.setScrollPosition(targetFrameViewPosition);
+    DoublePoint targetFrameViewPosition = m_rootFrameView->scrollPositionDouble() + DoubleSize(delta);
+    m_rootFrameView->setScrollPosition(targetFrameViewPosition);
 
-    DoubleSize remainder = targetFrameViewPosition - m_rootFrameView.scrollPositionDouble();
-    m_pinchViewport.move(toFloatSize(remainder));
+    DoubleSize remainder = targetFrameViewPosition - m_rootFrameView->scrollPositionDouble();
+    m_pinchViewport->move(toFloatSize(remainder));
 }
 
 } // namespace blink