Expand PaintLayer clip to account for hidden URL bar with document.rootScroller

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

Index: third_party/WebKit/Source/web/tests/RootScrollerTest.cpp
diff --git a/third_party/WebKit/Source/web/tests/RootScrollerTest.cpp b/third_party/WebKit/Source/web/tests/RootScrollerTest.cpp
index 230727d51733a778b4330c06332876ffffbc32b4..5f4e912ccff293363ada7b985d66724254a3c741 100644
--- a/third_party/WebKit/Source/web/tests/RootScrollerTest.cpp
+++ b/third_party/WebKit/Source/web/tests/RootScrollerTest.cpp
@@ -24,6 +24,7 @@
 #include "public/platform/WebURLLoaderMockFactory.h"
 #include "public/web/WebCache.h"
 #include "public/web/WebConsoleMessage.h"
+#include "public/web/WebHitTestResult.h"
 #include "public/web/WebRemoteFrame.h"
 #include "public/web/WebScriptSource.h"
 #include "public/web/WebSettings.h"
@@ -1316,6 +1317,228 @@ TEST_F(RootScrollerTest, ImmediateUpdateOfLayoutViewport) {
             &mainFrameView()->getRootFrameViewport()->layoutViewport());
 }
 
+class RootScrollerHitTest : public RootScrollerTest {
+ public:
+  void checkHitTestAtBottomOfScreen() {
+    // Hide the top controls and scroll down maximally.
+    {
+      webViewImpl()->handleInputEvent(
+          generateTouchGestureEvent(WebInputEvent::GestureScrollBegin));
+      ASSERT_EQ(1, browserControls().shownRatio());
+      webViewImpl()->handleInputEvent(generateTouchGestureEvent(
+          WebInputEvent::GestureScrollUpdate, 0, -browserControls().height()));
+      ASSERT_EQ(0, browserControls().shownRatio());
+      webViewImpl()->handleInputEvent(generateTouchGestureEvent(
+          WebInputEvent::GestureScrollUpdate, 0, -3000));
+      webViewImpl()->handleInputEvent(
+          generateTouchGestureEvent(WebInputEvent::GestureScrollEnd));
+      webViewImpl()->resizeWithBrowserControls(IntSize(400, 450), 50, false);
+    }
+
+    mainFrameView()->updateAllLifecyclePhases();
+
+    // Do a hit test at the very bottom of the screen. This should be outside
+    // the
+    // root scroller's LayoutBox since inert top controls won't resize the ICB
+    // but,
+    // since we expaned the clip, we should still be able to hit the target.
+    WebPoint point(200, 445);
+    WebSize tapArea(20, 20);
+    WebHitTestResult result =
+        webViewImpl()->hitTestResultForTap(point, tapArea);
+
+    ASSERT_TRUE(result.node());
+    EXPECT_EQ("target",
+              result.node().to<WebElement>().getAttribute("id").utf8());
+  }
+};
+
+// Test that hit testing in the area revealed at the bottom of the screen
+// revealed by hiding the URL bar works properly when using a root scroller
+// when the target and scroller are in the same PaintLayer.
+TEST_F(RootScrollerHitTest, HitTestInAreaRevealedByURLBarSameLayer) {
+  bool oldInertTopControls = RuntimeEnabledFeatures::inertTopControlsEnabled();
+  RuntimeEnabledFeatures::setInertTopControlsEnabled(true);
+
+  // Add a target at the bottom of the root scroller that's the size of the url
+  // bar. We'll test that hiding the URL bar appropriately adjusts clipping so
+  // that we can hit this target.
+  initialize("root-scroller.html");
+  executeScript(
+      "var target = document.createElement('div');"
+      "target.style.width = '100%';"
+      "target.style.height = '50px';"
+      "target.id = 'target';"
+      "document.getElementById('container').appendChild(target);");
+
+  Document* document = mainFrame()->document();
+  Element* container = document->getElementById("container");
+  Element* target = document->getElementById("target");
+  DummyExceptionStateForTesting exceptionState;
+  document->setRootScroller(container, exceptionState);
+
+  // This test checks hit testing while the target is in the same PaintLayer as
+  // the root scroller.
+  ASSERT_EQ(toLayoutBox(target->layoutObject())->enclosingLayer(),
+            toLayoutBox(container->layoutObject())->layer());
+
+  checkHitTestAtBottomOfScreen();
+
+  RuntimeEnabledFeatures::setInertTopControlsEnabled(oldInertTopControls);
+}
+
+// Test that hit testing in the area revealed at the bottom of the screen
+// revealed by hiding the URL bar works properly when using a root scroller
+// when the target and scroller are in different PaintLayers.
+TEST_F(RootScrollerHitTest, HitTestInAreaRevealedByURLBarDifferentLayer) {
+  bool oldInertTopControls = RuntimeEnabledFeatures::inertTopControlsEnabled();
+  RuntimeEnabledFeatures::setInertTopControlsEnabled(true);
+
+  // Add a target at the bottom of the root scroller that's the size of the url
+  // bar. We'll test that hiding the URL bar appropriately adjusts clipping so
+  // that we can hit this target.
+  initialize("root-scroller.html");
+  executeScript(
+      "var target = document.createElement('div');"
+      "target.style.width = '100%';"
+      "target.style.height = '50px';"
+      "target.style.willChange = 'transform';"
+      "target.id = 'target';"
+      "document.getElementById('container').appendChild(target);");
+
+  Document* document = mainFrame()->document();
+  Element* container = document->getElementById("container");
+  Element* target = document->getElementById("target");
+  DummyExceptionStateForTesting exceptionState;
+  document->setRootScroller(container, exceptionState);
+
+  // Ensure the target and container weren't put into the same layer.
+  ASSERT_NE(toLayoutBox(target->layoutObject())->enclosingLayer(),
+            toLayoutBox(container->layoutObject())->layer());
+
+  checkHitTestAtBottomOfScreen();
+
+  RuntimeEnabledFeatures::setInertTopControlsEnabled(oldInertTopControls);
+}
+
+// Test that hit testing in the area revealed at the bottom of the screen
+// revealed by hiding the URL bar works properly when using a root scroller
+// inside an iframe and the target is in the same paint layer as the scroller.
+TEST_F(RootScrollerHitTest, HitTestInAreaRevealedByURLBarIframeSameLayer) {
+  bool oldInertTopControls = RuntimeEnabledFeatures::inertTopControlsEnabled();
+  RuntimeEnabledFeatures::setInertTopControlsEnabled(true);
+
+  // Add a target at the bottom of the root scroller that's the size of the url
+  // bar. We'll test that hiding the URL bar appropriately adjusts clipping so
+  // that we can hit this target.
+  initialize("root-scroller-iframe.html");
+  WebLocalFrame* childWebFrame =
+      mainWebFrame()->firstChild()->toWebLocalFrame();
+  executeScript(
+      "var target = document.createElement('div');"
+      "target.style.width = '100%';"
+      "target.style.height = '50px';"
+      "target.id = 'target';"
+      "document.getElementById('container').appendChild(target);",
+      *childWebFrame);
+
+  Element* iframe = mainFrame()->document()->getElementById("iframe");
+  LocalFrame* childFrame =
+      toLocalFrame(toHTMLFrameOwnerElement(iframe)->contentFrame());
+
+  Document* childDocument = childFrame->document();
+  Element* container = childDocument->getElementById("container");
+  Element* target = childDocument->getElementById("target");
+  DummyExceptionStateForTesting exceptionState;
+  childDocument->setRootScroller(container, exceptionState);
+  mainFrame()->document()->setRootScroller(iframe, exceptionState);
+
+  // This test checks hit testing while the target is in the same PaintLayer as
+  // the root scroller.
+  ASSERT_EQ(toLayoutBox(target->layoutObject())->enclosingLayer(),
+            toLayoutBox(container->layoutObject())->layer());
+
+  checkHitTestAtBottomOfScreen();
+
+  RuntimeEnabledFeatures::setInertTopControlsEnabled(oldInertTopControls);
+}
+
+// Test that hit testing in the area revealed at the bottom of the screen
+// revealed by hiding the URL bar works properly when using a root scroller
+// inside an iframe and the target is in a different PaintLayer as the scroller.
+TEST_F(RootScrollerHitTest, HitTestInAreaRevealedByURLBarIframeDifferentLayer) {
+  bool oldInertTopControls = RuntimeEnabledFeatures::inertTopControlsEnabled();
+  RuntimeEnabledFeatures::setInertTopControlsEnabled(true);
+
+  // Add a target at the bottom of the root scroller that's the size of the url
+  // bar. We'll test that hiding the URL bar appropriately adjusts clipping so
+  // that we can hit this target.
+  initialize("root-scroller-iframe.html");
+  WebLocalFrame* childWebFrame =
+      mainWebFrame()->firstChild()->toWebLocalFrame();
+  executeScript(
+      "var target = document.createElement('div');"
+      "target.style.width = '100%';"
+      "target.style.height = '50px';"
+      "target.style.willChange = 'transform';"
+      "target.id = 'target';"
+      "document.getElementById('container').appendChild(target);",
+      *childWebFrame);
+
+  Element* iframe = mainFrame()->document()->getElementById("iframe");
+  LocalFrame* childFrame =
+      toLocalFrame(toHTMLFrameOwnerElement(iframe)->contentFrame());
+
+  Document* childDocument = childFrame->document();
+  Element* container = childDocument->getElementById("container");
+  Element* target = childDocument->getElementById("target");
+  DummyExceptionStateForTesting exceptionState;
+  childDocument->setRootScroller(container, exceptionState);
+  mainFrame()->document()->setRootScroller(iframe, exceptionState);
+
+  // This test checks hit testing while the target is in a different PaintLayer
+  // as the root scroller (ensured by will-change style).
+  ASSERT_NE(toLayoutBox(target->layoutObject())->enclosingLayer(),
+            toLayoutBox(container->layoutObject())->layer());
+
+  checkHitTestAtBottomOfScreen();
+
+  RuntimeEnabledFeatures::setInertTopControlsEnabled(oldInertTopControls);
+}
+
+// Test that hit testing in the area revealed at the bottom of the screen
+// revealed by hiding the URL bar works properly when using a iframe itself as
+// the root scroller.
+TEST_F(RootScrollerHitTest, HitTestInAreaRevealedByURLBarIframeRootScroller) {
+  bool oldInertTopControls = RuntimeEnabledFeatures::inertTopControlsEnabled();
+  RuntimeEnabledFeatures::setInertTopControlsEnabled(true);
+
+  // Add a target at the bottom of the root scroller that's the size of the url
+  // bar. We'll test that hiding the URL bar appropriately adjusts clipping so
+  // that we can hit this target.
+  initialize("root-scroller-iframe.html");
+  WebLocalFrame* childWebFrame =
+      mainWebFrame()->firstChild()->toWebLocalFrame();
+  executeScript(
+      "var target = document.createElement('div');"
+      "target.style.width = '100%';"
+      "target.style.height = '50px';"
+      "target.id = 'target';"
+      "document.getElementById('container').innerHTML = '';"
+      "document.getElementById('container').style.height = '200%';"
+      "document.body.appendChild(target);",
+      *childWebFrame);
+
+  Element* iframe = mainFrame()->document()->getElementById("iframe");
+
+  DummyExceptionStateForTesting exceptionState;
+  mainFrame()->document()->setRootScroller(iframe, exceptionState);
+
+  checkHitTestAtBottomOfScreen();
+
+  RuntimeEnabledFeatures::setInertTopControlsEnabled(oldInertTopControls);
+}
+
 }  // namespace
 
 }  // namespace blink