[Android WebView] Treat zero values in viewport arguments specially

Source/web/tests/WebFrameTest.cpp

Index: Source/web/tests/WebFrameTest.cpp
diff --git a/Source/web/tests/WebFrameTest.cpp b/Source/web/tests/WebFrameTest.cpp
index ca5c2fd80ac21caab25b132900d921d0673c4803..f516d0c713906c698cf88cafb9ce92730d0eb9a7 100644
--- a/Source/web/tests/WebFrameTest.cpp
+++ b/Source/web/tests/WebFrameTest.cpp
@@ -706,13 +706,39 @@ TEST_F(WebFrameTest, WideViewportInitialScaleDoesNotExpandFixedLayoutWidth)
     m_webView->settings()->setViewportEnabled(true);
     m_webView->settings()->setUseWideViewport(true);
     m_webView->settings()->setSupportDeprecatedTargetDensityDPI(true);
-    m_webView->settings()->setViewportMetaLayoutSizeQuirk(true);
+    m_webView->settings()->setViewportMetaLayoutSizeAndZeroValuesQuirk(true);
     m_webView->resize(WebSize(viewportWidth, viewportHeight));
 
     WebViewImpl* webViewImpl = static_cast<WebViewImpl*>(m_webView);
     EXPECT_EQ(viewportWidth, webViewImpl->mainFrameImpl()->frameView()->fixedLayoutSize().width());
 }
 
+TEST_F(WebFrameTest, ZeroValuesQuirk)
+{
+    registerMockedHttpURLLoad("viewport-zero-values.html");
+
+    FixedLayoutTestWebViewClient client;
+    client.m_screenInfo.deviceScaleFactor = 1;
+    int viewportWidth = 640;
+    int viewportHeight = 480;
+
+    m_webView = FrameTestHelpers::createWebViewAndLoad(m_baseURL + "viewport-zero-values.html", true, 0, &client);
+    m_webView->enableFixedLayoutMode(true);
+    m_webView->settings()->setViewportEnabled(true);
+    m_webView->settings()->setSupportDeprecatedTargetDensityDPI(true);
+    m_webView->settings()->setViewportMetaLayoutSizeAndZeroValuesQuirk(true);
+    m_webView->resize(WebSize(viewportWidth, viewportHeight));
+
+    WebViewImpl* webViewImpl = static_cast<WebViewImpl*>(m_webView);
+    EXPECT_EQ(viewportWidth, webViewImpl->mainFrameImpl()->frameView()->fixedLayoutSize().width());
+    EXPECT_EQ(1.0f, m_webView->pageScaleFactor());
+
+    m_webView->settings()->setUseWideViewport(true);
+    m_webView->layout();
+    EXPECT_EQ(viewportWidth, webViewImpl->mainFrameImpl()->frameView()->fixedLayoutSize().width());
+    EXPECT_EQ(1.0f, m_webView->pageScaleFactor());
+}
+
 TEST_F(WebFrameTest, ScaleFactorShouldNotOscillate)
 {
     registerMockedHttpURLLoad("scale_oscillate.html");