Avoid auto-resize re-entrancy problems.

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 64 matching lines @@
 #include "third_party/skia/include/core/SkBitmapDevice.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "web/WebLocalFrameImpl.h"
 #include "web/WebSettingsImpl.h"
 #include "web/WebViewImpl.h"
 #include "web/tests/FrameTestHelpers.h"
 #include "web/tests/URLTestHelpers.h"
 #include <gtest/gtest.h>
 
 using namespace blink;
+using blink::FrameTestHelpers::loadFrame;
 using blink::FrameTestHelpers::runPendingTasks;
 using blink::URLTestHelpers::toKURL;
 
 namespace {
 
 enum HorizontalScrollbarState {
     NoHorizontalScrollbar,
     VisibleHorizontalScrollbar,
 };
 
@@ skipping 2053 matching lines @@
 
     WebLocalFrameImpl* frame = toWebLocalFrameImpl(webView->mainFrame());
     frame->executeScript(WebScriptSource(WebString::fromUTF8("document.execCommand('SelectAll', false, null)")));
     std::string actual = frame->selectionAsText().utf8();
 
     const int kMaxOutputCharacters = 1024;
     std::string expected = frame->contentAsText(kMaxOutputCharacters).utf8();
     EXPECT_EQ(expected, actual);
 }
 
+TEST_F(WebViewTest, AutoResizeSubtreeLayout)

[levin, 2014/08/22 02:11:00]

If you care about this area, and you seem to, there are at least ~4 disabled
test in WebViewTest related to AutoSize. 

They all got disabled well after I stopped working on Chrome, but it would be
awesome if someone got them turned back on. (It would provide more confidence in
this feature continuing to work.)

[rune, 2014/08/22 08:52:26]

They pass for me when I enable them locally.

Running them through some bots now: https://codereview.chromium.org/500453003

+{
+    std::string url = m_baseURL + "subtree-layout.html";
+    URLTestHelpers::registerMockedURLLoad(toKURL(url), "subtree-layout.html");
+    WebView* webView = m_webViewHelper.initialize(true);
+
+    webView->enableAutoResizeMode(WebSize(200, 200), WebSize(200, 200));
+    loadFrame(webView->mainFrame(), url);
+
+    blink::FrameView* frameView = m_webViewHelper.webViewImpl()->mainFrameImpl()->frameView();
+
+    // Auto-resizing used to ASSERT(needsLayout()) in RenderBlockFlow::layout. This EXPECT is
+    // merely a dummy. The real test is that we don't trigger asserts in debug builds.
+    EXPECT_FALSE(frameView->needsLayout());
+};
+
 } // namespace