Make sure resent events that don't match ids are not coalesced.

ui/events/blink/blink_event_util_unittest.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/events/blink/blink_event_util.h"
 
 #include "base/time/time.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/WebKit/public/platform/WebGestureEvent.h"
 #include "third_party/WebKit/public/platform/WebInputEvent.h"
@@ skipping 137 matching lines @@
   touch_point.movementY = -4;
   event_to_be_coalesced.touches[event_to_be_coalesced.touchesLength++] =
       touch_point;
 
   EXPECT_TRUE(CanCoalesce(event_to_be_coalesced, coalesced_event));
   Coalesce(event_to_be_coalesced, &coalesced_event);
   EXPECT_EQ(8, coalesced_event.touches[0].movementX);
   EXPECT_EQ(6, coalesced_event.touches[0].movementY);
 }
 
+TEST(BlinkEventUtilTest, WebMouseWheelEventCoalescing) {
+  blink::WebMouseWheelEvent coalesced_event(
+      blink::WebInputEvent::MouseWheel, blink::WebInputEvent::NoModifiers,
+      blink::WebInputEvent::TimeStampForTesting);
+  coalesced_event.deltaX = 1;
+  coalesced_event.deltaY = 1;
+
+  blink::WebMouseWheelEvent event_to_be_coalesced(
+      blink::WebInputEvent::MouseWheel, blink::WebInputEvent::NoModifiers,
+      blink::WebInputEvent::TimeStampForTesting);
+  event_to_be_coalesced.deltaX = 3;
+  event_to_be_coalesced.deltaY = 4;
+
+  EXPECT_TRUE(CanCoalesce(event_to_be_coalesced, coalesced_event));
+  Coalesce(event_to_be_coalesced, &coalesced_event);
+  EXPECT_EQ(4, coalesced_event.deltaX);
+  EXPECT_EQ(5, coalesced_event.deltaY);
+
+  event_to_be_coalesced.resendingPluginId = 3;
+  EXPECT_FALSE(CanCoalesce(event_to_be_coalesced, coalesced_event));
+}
+
+TEST(BlinkEventUtilTest, WebGestureEventCoalescing) {
+  blink::WebGestureEvent coalesced_event(
+      blink::WebInputEvent::GestureScrollUpdate,
+      blink::WebInputEvent::NoModifiers,
+      blink::WebInputEvent::TimeStampForTesting);
+  coalesced_event.data.scrollUpdate.deltaX = 1;
+  coalesced_event.data.scrollUpdate.deltaY = 1;
+
+  blink::WebGestureEvent event_to_be_coalesced(
+      blink::WebInputEvent::GestureScrollUpdate,
+      blink::WebInputEvent::NoModifiers,
+      blink::WebInputEvent::TimeStampForTesting);
+  event_to_be_coalesced.data.scrollUpdate.deltaX = 3;
+  event_to_be_coalesced.data.scrollUpdate.deltaY = 4;
+
+  EXPECT_TRUE(CanCoalesce(event_to_be_coalesced, coalesced_event));
+  Coalesce(event_to_be_coalesced, &coalesced_event);
+  EXPECT_EQ(4, coalesced_event.data.scrollUpdate.deltaX);
+  EXPECT_EQ(5, coalesced_event.data.scrollUpdate.deltaY);
+
+  event_to_be_coalesced.resendingPluginId = 3;
+  EXPECT_FALSE(CanCoalesce(event_to_be_coalesced, coalesced_event));
+}
+
 }  // namespace ui