Oilpan: move HistoryItem to the heap.

Source/web/tests/PinchViewportTest.cpp

 // Copyright 2014 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 "core/frame/PinchViewport.h"
 
 #include "core/frame/FrameHost.h"
 #include "core/frame/LocalFrame.h"
@@ skipping 763 matching lines @@
     frameView->setScrollOffset(IntPoint(0, 1000));
 
     // The frameView should be 1000x1000 since the viewport meta width=1000 and
     // the aspect ratio is 1:1.
     EXPECT_SIZE_EQ(IntSize(1000, 1000), frameView->frameRect().size());
 
     PinchViewport& pinchViewport = frame()->page()->frameHost().pinchViewport();
     pinchViewport.setScale(2);
     pinchViewport.setLocation(FloatPoint(950, 950));
 
-    RefPtr<HistoryItem> firstItem = webViewImpl()->mainFrameImpl()->frame()->loader().currentItem();
+    RefPtrWillBePersistent<HistoryItem> firstItem = webViewImpl()->mainFrameImpl()->frame()->loader().currentItem();
     EXPECT_POINT_EQ(IntPoint(0, 1000), firstItem->scrollPoint());
 
     // Now navigate to a page which causes a smaller frameView. Make sure that
     // navigating doesn't cause the history item to set a new scroll offset
     // before the item was replaced.
     navigateTo("about:blank");
     frameView = webViewImpl()->mainFrameImpl()->frameView();
 
     EXPECT_NE(firstItem, webViewImpl()->mainFrameImpl()->frame()->loader().currentItem());
     EXPECT_LT(frameView->frameRect().size().width(), 1000);
@@ skipping 372 matching lines @@
     FrameView& frameView = *webViewImpl()->mainFrameImpl()->frameView();
     WebLayer* scrollLayer = frameView.layerForScrolling()->platformLayer();
 
     frameView.setContentsSize(IntSize(1500, 2400));
     frameView.updateLayoutAndStyleForPainting();
 
     EXPECT_SIZE_EQ(IntSize(1500, 2400), IntSize(scrollLayer->bounds()));
 }
 
 } // namespace