Refactor frame navigation/detach state cleanup to be more sane.

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/dom/Document.h"
 #include "core/frame/FrameHost.h"
@@ skipping 1529 matching lines @@
 TEST_F(PinchViewportTest, TestMainFrameInitializationSizing)
 {
     initializeWithAndroidSettings();
 
     webViewImpl()->resize(IntSize(100, 200));
 
     registerMockedHttpURLLoad("content-width-1000-min-scale.html");
     navigateTo(m_baseURL + "content-width-1000-min-scale.html");
 
     WebLocalFrameImpl* localFrame = webViewImpl()->mainFrameImpl();
+    // The prepareForDestruction() and prepareForDetach() calls are a hack to
+    // prevent createView() from violating invariants about frame state during
+    // navigation/detach.
+    localFrame->frame()->document()->prepareForDestruction();
     localFrame->createFrameView();
 
     FrameView& frameView = *localFrame->frameView();
     EXPECT_SIZE_EQ(IntSize(200, 400), frameView.frameRect().size());
+    frameView.prepareForDetach();
 }
 
 // Tests that the maximum scroll offset of the viewport can be fractional.
 TEST_F(PinchViewportTest, FractionalMaxScrollOffset)
 {
     initializeWithDesktopSettings();
     webViewImpl()->resize(IntSize(101, 201));
     navigateTo("about:blank");
 
     PinchViewport& pinchViewport = frame()->page()->frameHost().pinchViewport();
@@ skipping 102 matching lines @@
     EXPECT_FLOAT_POINT_EQ(FloatPoint(81, 100.8), pinchViewport.rootFrameToViewport(FloatPoint(50.5, 62.4)));
 
 
     // Scrolling the main frame should have no effect.
     frameView.scrollTo(DoublePoint(100, 120));
     EXPECT_FLOAT_POINT_EQ(FloatPoint(50, 62), pinchViewport.viewportToRootFrame(FloatPoint(80, 100)));
     EXPECT_FLOAT_POINT_EQ(FloatPoint(80, 100), pinchViewport.rootFrameToViewport(FloatPoint(50, 62)));
 }
 
 } // namespace