Reland of Don't change layout size due to top control show/hide

third_party/WebKit/Source/web/tests/TopControlsTest.cpp

Index: third_party/WebKit/Source/web/tests/TopControlsTest.cpp
diff --git a/third_party/WebKit/Source/web/tests/TopControlsTest.cpp b/third_party/WebKit/Source/web/tests/TopControlsTest.cpp
index c81cd278c74753bc76b7cdc33eafa6cd23ffdcee..5ed7c95296884dff751058108392aaca81f6ffd0 100644
--- a/third_party/WebKit/Source/web/tests/TopControlsTest.cpp
+++ b/third_party/WebKit/Source/web/tests/TopControlsTest.cpp
@@ -29,6 +29,7 @@
  */
 #include "core/frame/TopControls.h"
 
+#include "core/dom/ClientRect.h"
 #include "core/frame/FrameHost.h"
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
@@ -37,6 +38,7 @@
 #include "platform/testing/URLTestHelpers.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebUnitTestSupport.h"
+#include "public/web/WebElement.h"
 #include "public/web/WebSettings.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -57,6 +59,10 @@
         registerMockedHttpURLLoad("overflow-scrolling.html");
         registerMockedHttpURLLoad("iframe-scrolling.html");
         registerMockedHttpURLLoad("iframe-scrolling-inner.html");
+        registerMockedHttpURLLoad("percent-height.html");
+        registerMockedHttpURLLoad("vh-height.html");
+        registerMockedHttpURLLoad("vh-height-width-800.html");
+        registerMockedHttpURLLoad("vh-height-width-800-extra-wide.html");
     }
 
     ~TopControlsTest() override
@@ -112,6 +118,13 @@
         webViewImpl()->handleInputEvent(generateEvent(WebInputEvent::GestureScrollEnd));
     }
 
+    PassRefPtrWillBeRawPtr<Element> getElementById(const WebString& id)
+    {
+        return static_cast<PassRefPtrWillBeRawPtr<Element>>(
+            webViewImpl()->mainFrame()->document().getElementById(id));
+    }
+
+
     WebViewImpl* webViewImpl() const { return m_helper.webViewImpl(); }
     LocalFrame* frame() const { return m_helper.webViewImpl()->mainFrameImpl()->frame(); }
     VisualViewport& visualViewport() const { return m_helper.webViewImpl()->page()->frameHost().visualViewport(); }
@@ -544,4 +557,176 @@
     EXPECT_POINT_EQ(IntPoint(0, 90), frame()->view()->scrollPosition());
 }
 
+// Ensure that top controls do not affect the layout by showing and hiding
+// except for position: fixed elements.
+TEST_F(TopControlsTest, MAYBE(DontAffectLayoutHeight))
+{
+    // Initialize with the top controls showing.
+    WebViewImpl* webView = initialize("percent-height.html");
+    webView->setTopControlsHeight(100.f, true);
+    webView->updateTopControlsState(
+        WebTopControlsBoth, WebTopControlsShown, false);
+    webView->topControls().setShownRatio(1);
+    webView->resize(WebSize(400, 300));
+    webView->updateAllLifecyclePhases();
+
+    ASSERT_EQ(100.f, webView->topControls().contentOffset());
+
+    // When the top controls are showing, there's 300px for the layout height so
+    // 50% should result in both the position:fixed and position: absolute divs
+    // having 150px of height.
+    RefPtrWillBeRawPtr<Element> absPos =
+        getElementById(WebString::fromUTF8("abs"));
+    RefPtrWillBeRawPtr<Element> fixedPos =
+        getElementById(WebString::fromUTF8("fixed"));
+    EXPECT_FLOAT_EQ(150.f, absPos->getBoundingClientRect()->height());
+    EXPECT_FLOAT_EQ(150.f, fixedPos->getBoundingClientRect()->height());
+
+    // The layout size on the FrameView should not include the top controls.
+    EXPECT_EQ(300, frame()->view()->layoutSize(IncludeScrollbars).height());
+
+    // Hide the top controls.
+    verticalScroll(-100.f);
+    webView->setTopControlsHeight(100.f, false);
+    webView->resize(WebSize(400, 400));
+    webView->updateAllLifecyclePhases();
+
+    ASSERT_EQ(0.f, webView->topControls().contentOffset());
+
+    // Hiding the top controls shouldn't change the height of the initial
+    // containing block for non-position: fixed. Position: fixed however should
+    // use the entire height of the viewport however.
+    EXPECT_FLOAT_EQ(150.f, absPos->getBoundingClientRect()->height());
+    EXPECT_FLOAT_EQ(200.f, fixedPos->getBoundingClientRect()->height());
+
+    // The layout size should not change as a result of top controls hiding.
+    EXPECT_EQ(300, frame()->view()->layoutSize(IncludeScrollbars).height());
+}
+
+// Ensure that top controls do not affect vh units.
+TEST_F(TopControlsTest, MAYBE(DontAffectVHUnits))
+{
+    // Initialize with the top controls showing.
+    WebViewImpl* webView = initialize("vh-height.html");
+    webView->setTopControlsHeight(100.f, true);
+    webView->updateTopControlsState(
+        WebTopControlsBoth, WebTopControlsShown, false);
+    webView->topControls().setShownRatio(1);
+    webView->resize(WebSize(400, 300));
+    webView->updateAllLifecyclePhases();
+
+    ASSERT_EQ(100.f, webView->topControls().contentOffset());
+
+    // 'vh' units should be based on the viewport when the top controls are
+    // hidden.
+    RefPtrWillBeRawPtr<Element> absPos =
+        getElementById(WebString::fromUTF8("abs"));
+    RefPtrWillBeRawPtr<Element> fixedPos =
+        getElementById(WebString::fromUTF8("fixed"));
+    EXPECT_FLOAT_EQ(200.f, absPos->getBoundingClientRect()->height());
+    EXPECT_FLOAT_EQ(200.f, fixedPos->getBoundingClientRect()->height());
+
+    // The size used for viewport units should not be reduced by the top
+    // controls.
+    EXPECT_EQ(400, frame()->view()->viewportSizeForViewportUnits().height());
+
+    // Hide the top controls.
+    verticalScroll(-100.f);
+    webView->setTopControlsHeight(100.f, false);
+    webView->resize(WebSize(400, 400));
+    webView->updateAllLifecyclePhases();
+
+    ASSERT_EQ(0.f, webView->topControls().contentOffset());
+
+    // vh units should be static with respect to the top controls so neighter
+    // <div> should change size are a result of the top controls hiding.
+    EXPECT_FLOAT_EQ(200.f, absPos->getBoundingClientRect()->height());
+    EXPECT_FLOAT_EQ(200.f, fixedPos->getBoundingClientRect()->height());
+
+    // The viewport size used for vh units should not change as a result of top
+    // controls hiding.
+    EXPECT_EQ(400, frame()->view()->viewportSizeForViewportUnits().height());
+}
+
+// Ensure that on a legacy page (there's a non-1 minimum scale) 100vh units fill
+// the viewport, with top controls hidden, when the viewport encompasses the
+// layout width.
+TEST_F(TopControlsTest, MAYBE(DontAffectVHUnitsWithScale))
+{
+    // Initialize with the top controls showing.
+    WebViewImpl* webView = initialize("vh-height-width-800.html");
+    webView->setTopControlsHeight(100.f, true);
+    webView->updateTopControlsState(
+        WebTopControlsBoth, WebTopControlsShown, false);
+    webView->topControls().setShownRatio(1);
+    webView->resize(WebSize(400, 300));
+    webView->updateAllLifecyclePhases();
+
+    ASSERT_EQ(100.f, webView->topControls().contentOffset());
+
+    // Device viewport is 400px but the page is width=800 so minimum-scale
+    // should be 0.5. This is also the scale at which the viewport fills the
+    // layout width.
+    ASSERT_EQ(0.5f, webView->minimumPageScaleFactor());
+
+    // We should size vh units so that 100vh fills the viewport at min-scale so
+    // we have to account for the minimum page scale factor. Since both boxes
+    // are 50vh, and layout scale = 0.5, we have a vh viewport of 400 / 0.5 = 800
+    // so we expect 50vh to be 400px.
+    RefPtrWillBeRawPtr<Element> absPos =
+        getElementById(WebString::fromUTF8("abs"));
+    RefPtrWillBeRawPtr<Element> fixedPos =
+        getElementById(WebString::fromUTF8("fixed"));
+    EXPECT_FLOAT_EQ(400.f, absPos->getBoundingClientRect()->height());
+    EXPECT_FLOAT_EQ(400.f, fixedPos->getBoundingClientRect()->height());
+
+    // The size used for viewport units should not be reduced by the top
+    // controls.
+    EXPECT_EQ(800, frame()->view()->viewportSizeForViewportUnits().height());
+
+    // Hide the top controls.
+    verticalScroll(-100.f);
+    webView->setTopControlsHeight(100.f, false);
+    webView->resize(WebSize(400, 400));
+    webView->updateAllLifecyclePhases();
+
+    ASSERT_EQ(0.f, webView->topControls().contentOffset());
+
+    // vh units should be static with respect to the top controls so neighter
+    // <div> should change size are a result of the top controls hiding.
+    EXPECT_FLOAT_EQ(400.f, absPos->getBoundingClientRect()->height());
+    EXPECT_FLOAT_EQ(400.f, fixedPos->getBoundingClientRect()->height());
+
+    // The viewport size used for vh units should not change as a result of top
+    // controls hiding.
+    EXPECT_EQ(800, frame()->view()->viewportSizeForViewportUnits().height());
+}
+
+// Ensure that on a legacy page (there's a non-1 minimum scale) whose viewport
+// at minimum-scale is larger than the layout size, 100vh units fill the
+// viewport, with top controls hidden, when the viewport is scaled such that
+// its width equals the layout width.
+TEST_F(TopControlsTest, MAYBE(DontAffectVHUnitsUseLayoutSize))
+{
+    // Initialize with the top controls showing.
+    WebViewImpl* webView = initialize("vh-height-width-800-extra-wide.html");
+    webView->setTopControlsHeight(100.f, true);
+    webView->updateTopControlsState(
+        WebTopControlsBoth, WebTopControlsShown, false);
+    webView->topControls().setShownRatio(1);
+    webView->resize(WebSize(400, 300));
+    webView->updateAllLifecyclePhases();
+
+    ASSERT_EQ(100.f, webView->topControls().contentOffset());
+
+    // Device viewport is 400px and page is width=800 but there's an element
+    // that's 1600px wide so the minimum scale is 0.25 to encompass that.
+    ASSERT_EQ(0.25f, webView->minimumPageScaleFactor());
+
+    // The viewport will match the layout width at scale=0.5 so the height used
+    // for vh should be (300 / 0.5) for the layout height + (100 / 0.5) for top
+    // controls = 800.
+    EXPECT_EQ(800, frame()->view()->viewportSizeForViewportUnits().height());
+}
+
 } // namespace blink