Revert of Remove enable/disable wheel gestures setting.

ui/events/blink/input_handler_proxy_unittest.cc

Index: ui/events/blink/input_handler_proxy_unittest.cc
diff --git a/ui/events/blink/input_handler_proxy_unittest.cc b/ui/events/blink/input_handler_proxy_unittest.cc
index fbb5dddeba5a2f985936e50865c8870545ac2d72..c14d13f4f225a61601c3429f1a485368dbd90f06 100644
--- a/ui/events/blink/input_handler_proxy_unittest.cc
+++ b/ui/events/blink/input_handler_proxy_unittest.cc
@@ -385,6 +385,10 @@
     input_handler_->smooth_scroll_enabled_ = value;
   }
 
+  void SetMouseWheelGesturesOn(bool value) {
+    input_handler_->set_use_gesture_events_for_mouse_wheel(value);
+  }
+
   base::HistogramTester& histogram_tester() {
     return histogram_tester_;
   }
@@ -404,6 +408,28 @@
   cc::InputHandlerScrollResult scroll_result_did_not_scroll_;
 };
 
+TEST_P(InputHandlerProxyTest, MouseWheelByPageMainThread) {
+  expected_disposition_ = InputHandlerProxy::DID_NOT_HANDLE;
+  SetMouseWheelGesturesOn(false);
+  WebMouseWheelEvent wheel;
+  wheel.type = WebInputEvent::MouseWheel;
+  wheel.scrollByPage = true;
+
+  EXPECT_EQ(expected_disposition_, input_handler_->HandleInputEvent(wheel));
+  VERIFY_AND_RESET_MOCKS();
+}
+
+TEST_P(InputHandlerProxyTest, MouseWheelWithCtrlNotScroll) {
+  expected_disposition_ = InputHandlerProxy::DID_NOT_HANDLE;
+  SetMouseWheelGesturesOn(false);
+  WebMouseWheelEvent wheel;
+  wheel.type = WebInputEvent::MouseWheel;
+  wheel.modifiers = WebInputEvent::ControlKey;
+  wheel.canScroll = false;
+  EXPECT_EQ(expected_disposition_, input_handler_->HandleInputEvent(wheel));
+  VERIFY_AND_RESET_MOCKS();
+}
+
 TEST_P(InputHandlerProxyTest, MouseWheelNoListener) {
   expected_disposition_ = InputHandlerProxy::DROP_EVENT;
   EXPECT_CALL(mock_input_handler_,
@@ -439,6 +465,59 @@
   WebMouseWheelEvent wheel;
   wheel.type = WebInputEvent::MouseWheel;
   wheel.modifiers = WebInputEvent::ControlKey;
+  EXPECT_EQ(expected_disposition_, input_handler_->HandleInputEvent(wheel));
+  VERIFY_AND_RESET_MOCKS();
+}
+
+// Mac does not smooth scroll wheel events (crbug.com/574283).
+#if !defined(OS_MACOSX)
+TEST_P(InputHandlerProxyTest, MouseWheelWithPreciseScrollingDeltas) {
+#else
+TEST_P(InputHandlerProxyTest, DISABLED_MouseWheelWithPreciseScrollingDeltas) {
+#endif
+  SetSmoothScrollEnabled(true);
+  SetMouseWheelGesturesOn(false);
+  expected_disposition_ = InputHandlerProxy::DID_HANDLE;
+  WebMouseWheelEvent wheel;
+  wheel.type = WebInputEvent::MouseWheel;
+
+  VERIFY_AND_RESET_MOCKS();
+
+  // Smooth scroll because hasPreciseScrollingDeltas is set to false.
+  wheel.hasPreciseScrollingDeltas = false;
+  EXPECT_CALL(mock_input_handler_, ScrollAnimated(::testing::_, ::testing::_))
+      .WillOnce(testing::Return(kImplThreadScrollState));
+  EXPECT_EQ(expected_disposition_, input_handler_->HandleInputEvent(wheel));
+
+  VERIFY_AND_RESET_MOCKS();
+
+  // No smooth scroll because hasPreciseScrollingDeltas is set to true.
+  wheel.hasPreciseScrollingDeltas = true;
+  EXPECT_CALL(mock_input_handler_, ScrollBegin(::testing::_, ::testing::_))
+      .WillOnce(testing::Return(kImplThreadScrollState));
+  EXPECT_CALL(mock_input_handler_, ScrollBy(::testing::_))
+      .WillOnce(testing::Return(scroll_result_did_scroll_));
+  EXPECT_CALL(mock_input_handler_, ScrollEnd(testing::_));
+  EXPECT_EQ(expected_disposition_, input_handler_->HandleInputEvent(wheel));
+
+  VERIFY_AND_RESET_MOCKS();
+}
+
+// Mac does not smooth scroll wheel events (crbug.com/574283).
+#if !defined(OS_MACOSX)
+TEST_P(InputHandlerProxyTest, MouseWheelScrollIgnored) {
+#else
+TEST_P(InputHandlerProxyTest, DISABLED_MouseWheelScrollIgnored) {
+#endif
+  SetSmoothScrollEnabled(true);
+  SetMouseWheelGesturesOn(false);
+  expected_disposition_ = InputHandlerProxy::DROP_EVENT;
+  WebMouseWheelEvent wheel;
+  wheel.type = WebInputEvent::MouseWheel;
+
+  EXPECT_CALL(mock_input_handler_, ScrollAnimated(testing::_, testing::_))
+      .WillOnce(testing::Return(kScrollIgnoredScrollState));
+
   EXPECT_EQ(expected_disposition_, input_handler_->HandleInputEvent(wheel));
   VERIFY_AND_RESET_MOCKS();
 }