Invalidate touchEventTargetRects in ScrollingCoordinator when toggling touch emulation.

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

Index: third_party/WebKit/Source/web/tests/ScrollingCoordinatorTest.cpp
diff --git a/third_party/WebKit/Source/web/tests/ScrollingCoordinatorTest.cpp b/third_party/WebKit/Source/web/tests/ScrollingCoordinatorTest.cpp
index 12ebf904b6d06bc8173d091a6770b53d24d314b2..3feca74125d90c7b081f85879cb3333d2948788b 100644
--- a/third_party/WebKit/Source/web/tests/ScrollingCoordinatorTest.cpp
+++ b/third_party/WebKit/Source/web/tests/ScrollingCoordinatorTest.cpp
@@ -630,4 +630,20 @@ TEST_F(ScrollingCoordinatorTest, FixedPositionLosingBackingShouldTriggerMainThre
     EXPECT_TRUE(scrollLayer->shouldScrollOnMainThread());
 }
 
+TEST_F(ScrollingCoordinatorTest, TouchEventTargetRectsWithEmulatedTouch)
+{
+    RuntimeEnabledFeatures::setTouchEnabled(false);
+
+    registerMockedHttpURLLoad("touch-event-target-rects.html");
+    navigateTo(m_baseURL + "touch-event-target-rects.html");
+    forceFullCompositingUpdate();
+    ScrollingCoordinator* coordinator = webViewImpl()->page()->scrollingCoordinator();
+
+    EXPECT_EQ(0u, coordinator->touchEventTargetLayersCountForTest());
+    webViewImpl()->setTouchEventEmulationEnabled(true);
+    EXPECT_EQ(1u, coordinator->touchEventTargetLayersCountForTest());
+    webViewImpl()->setTouchEventEmulationEnabled(false);
+    EXPECT_EQ(0u, coordinator->touchEventTargetLayersCountForTest());
+}
+
 } // namespace blink