Add a force-layout-height-to-zero layout mode to WebViewImpl

Source/web/tests/WebFrameTest.cpp

 /*
  * Copyright (C) 2010 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 1353 matching lines @@
 
     EXPECT_EQ(viewportWidth, webViewHelper.webViewImpl()->mainFrameImpl()->frameView()->layoutSize().width());
     EXPECT_EQ(1, webViewHelper.webView()->pageScaleFactor());
 
     webViewHelper.webView()->setFixedLayoutSize(WebSize(2000, 1500));
     webViewHelper.webView()->layout();
     EXPECT_EQ(2000, webViewHelper.webViewImpl()->mainFrameImpl()->frameView()->layoutSize().width());
     EXPECT_EQ(0.5f, webViewHelper.webView()->pageScaleFactor());
 }
 
+TEST_F(WebFrameTest, SetForceZeroLayoutHeight)
+{
+    UseMockScrollbarSettings mockScrollbarSettings;
+    registerMockedHttpURLLoad("200-by-300.html");
+
+    FixedLayoutTestWebViewClient client;
+    client.m_screenInfo.deviceScaleFactor = 1;
+    int viewportWidth = 640;
+    int viewportHeight = 480;
+
+    FrameTestHelpers::WebViewHelper webViewHelper;
+
+    webViewHelper.initializeAndLoad(m_baseURL + "200-by-300.html", true, 0, &client, enableViewportSettings);
+    webViewHelper.webView()->resize(WebSize(viewportWidth, viewportHeight));
+    webViewHelper.webView()->layout();
+
+    EXPECT_EQ(viewportHeight, webViewHelper.webViewImpl()->mainFrameImpl()->frameView()->layoutSize().height());
+    webViewHelper.webView()->settings()->setForceZeroLayoutHeight(true);
+    EXPECT_TRUE(webViewHelper.webViewImpl()->mainFrameImpl()->frameView()->needsLayout());
+
+    EXPECT_EQ(0, webViewHelper.webViewImpl()->mainFrameImpl()->frameView()->layoutSize().height());
+
+    webViewHelper.webView()->resize(WebSize(viewportWidth, viewportHeight * 2));
+    EXPECT_FALSE(webViewHelper.webViewImpl()->mainFrameImpl()->frameView()->needsLayout());
+    EXPECT_EQ(0, webViewHelper.webViewImpl()->mainFrameImpl()->frameView()->layoutSize().height());
+
+    webViewHelper.webView()->resize(WebSize(viewportWidth * 2, viewportHeight));
+    webViewHelper.webView()->layout();
+    EXPECT_EQ(0, webViewHelper.webViewImpl()->mainFrameImpl()->frameView()->layoutSize().height());
+
+    webViewHelper.webView()->settings()->setForceZeroLayoutHeight(false);
+    EXPECT_EQ(viewportHeight, webViewHelper.webViewImpl()->mainFrameImpl()->frameView()->layoutSize().height());
+}
+
 TEST_F(WebFrameTest, WideViewportAndWideContentWithInitialScale)
 {
     UseMockScrollbarSettings mockScrollbarSettings;
     registerMockedHttpURLLoad("wide_document_width_viewport.html");
 
     FixedLayoutTestWebViewClient client;
     client.m_screenInfo.deviceScaleFactor = 1;
     int viewportWidth = 600;
     int viewportHeight = 800;
 
@@ skipping 4355 matching lines @@
     std::string content = localFrame->contentAsText(1024).utf8();
     EXPECT_EQ("hello", content);
 
     // Manually reset to break WebViewHelper's dependency on the stack allocated
     // TestWebFrameClient.
     reset();
     remoteFrame->close();
 }
 
 } // namespace