Don't reuse HistoryItems for multiple navigations

Source/web/tests/WebViewTest.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 1151 matching lines @@
     EXPECT_EQ(2.0f, webViewImpl->pageScaleFactor());
     EXPECT_EQ(94, webViewImpl->mainFrame()->scrollOffset().width);
     EXPECT_EQ(111, webViewImpl->mainFrame()->scrollOffset().height);
     LocalFrame* mainFrameLocal = toLocalFrame(webViewImpl->page()->mainFrame());
     mainFrameLocal->loader().saveScrollState();
     EXPECT_EQ(2.0f, mainFrameLocal->loader().currentItem()->pageScaleFactor());
     EXPECT_EQ(94, mainFrameLocal->loader().currentItem()->scrollPoint().x());
     EXPECT_EQ(111, mainFrameLocal->loader().currentItem()->scrollPoint().y());
 
     // Confirm that resetting the page state resets the saved scroll position.
-    // The HistoryController treats a page scale factor of 0.0f as special and avoids
-    // restoring it to the WebView.
     webViewImpl->resetScrollAndScaleState();
     EXPECT_EQ(1.0f, webViewImpl->pageScaleFactor());
     EXPECT_EQ(0, webViewImpl->mainFrame()->scrollOffset().width);
     EXPECT_EQ(0, webViewImpl->mainFrame()->scrollOffset().height);
-    EXPECT_EQ(0.0f, mainFrameLocal->loader().currentItem()->pageScaleFactor());
+    EXPECT_EQ(1.0f, mainFrameLocal->loader().currentItem()->pageScaleFactor());
     EXPECT_EQ(0, mainFrameLocal->loader().currentItem()->scrollPoint().x());
     EXPECT_EQ(0, mainFrameLocal->loader().currentItem()->scrollPoint().y());
 }
 
 TEST_F(WebViewTest, BackForwardRestoreScroll)
 {
     URLTestHelpers::registerMockedURLFromBaseURL(WebString::fromUTF8(m_baseURL.c_str()), WebString::fromUTF8("back_forward_restore_scroll.html"));
     WebViewImpl* webViewImpl = m_webViewHelper.initializeAndLoad(m_baseURL + "back_forward_restore_scroll.html");
     webViewImpl->resize(WebSize(640, 480));
     webViewImpl->layout();
@@ skipping 1830 matching lines @@
     for (size_t i = 0; i < renders.size(); ++i) {
         double docStartTime = frame->domWindow()->document()->loader()->timing().monotonicTimeToZeroBasedDocumentTime(renderPairs[i].startTime) * 1000.0;
         ASSERT_DOUBLE_EQ(docStartTime, renders[i]->startTime());
         double docFinishTime = frame->domWindow()->document()->loader()->timing().monotonicTimeToZeroBasedDocumentTime(renderPairs[i].finishTime) * 1000.0;
         double docDuration = docFinishTime - docStartTime;
         ASSERT_DOUBLE_EQ(docDuration, renders[i]->duration());
     }
 }
 
 } // namespace