MouseWheelEventQueue sends scrollEnd right away when latching is disabled.

content/browser/renderer_host/input/input_router_impl_unittest.cc

Index: content/browser/renderer_host/input/input_router_impl_unittest.cc
diff --git a/content/browser/renderer_host/input/input_router_impl_unittest.cc b/content/browser/renderer_host/input/input_router_impl_unittest.cc
index d0e5634de62f1413f986ab26731c366883ed32ab..4316530ca85f4b03251e2bff44c107ec312cd764 100644
--- a/content/browser/renderer_host/input/input_router_impl_unittest.cc
+++ b/content/browser/renderer_host/input/input_router_impl_unittest.cc
@@ -1032,13 +1032,35 @@ TEST_F(InputRouterImplTest, UnhandledWheelEvent) {
   EXPECT_EQ(ack_handler_->acked_wheel_event().deltaY, -5);
   SendInputEventACK(WebInputEvent::GestureScrollUpdate,
                     INPUT_EVENT_ACK_STATE_CONSUMED);
+
+  // There should be a ScrollEnd sent

[tdresser, 2017/03/29 16:55:32]

Missing "."

Same below.

[sahel, 2017/03/29 20:10:43]

Done.

+  EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
+
+  // Check that the ack for the ScrollUpdate and ScrollEnd
+  // were processed.
+  EXPECT_EQ(2U, ack_handler_->GetAndResetAckCount());
+
   SendInputEventACK(WebInputEvent::MouseWheel,
                     INPUT_EVENT_ACK_STATE_NOT_CONSUMED);
 
+  // There should be a ScrollBegin and ScrollUpdate sent
+  EXPECT_EQ(2U, GetSentMessageCountAndResetSink());
+
   // Check that the correct unhandled wheel event was received.
   EXPECT_EQ(2U, ack_handler_->GetAndResetAckCount());
-  EXPECT_EQ(INPUT_EVENT_ACK_STATE_NOT_CONSUMED, ack_handler_->ack_state());
+  EXPECT_EQ(INPUT_EVENT_ACK_STATE_NOT_CONSUMED,
+            ack_handler_->acked_wheel_event_state());
   EXPECT_EQ(ack_handler_->acked_wheel_event().deltaY, -10);
+
+  SendInputEventACK(WebInputEvent::GestureScrollUpdate,
+                    INPUT_EVENT_ACK_STATE_CONSUMED);
+
+  // There should be a ScrollEnd sent
+  EXPECT_EQ(1U, GetSentMessageCountAndResetSink());
+
+  // Check that the ack for the ScrollUpdate and ScrollEnd
+  // were processed.
+  EXPECT_EQ(2U, ack_handler_->GetAndResetAckCount());
 }
 
 TEST_F(InputRouterImplTest, TouchTypesIgnoringAck) {