Don't track mouse events in HWNDMessageHandler when they are forwarded by the LegacyRenderWidgetHost

base/win/win_util.h

 // Copyright (c) 2012 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.
 
 // =============================================================================
 // PLEASE READ
 //
 // In general, you should not be adding stuff to this file.
 //
 // - If your thing is only used in one place, just put it in a reasonable
@@ skipping 111 matching lines @@
 // success.
 BASE_EXPORT bool DisplayVirtualKeyboard();
 
 // Dismisses the on screen keyboard if it is being displayed on Windows 8 and.
 // above. Returns true on success.
 BASE_EXPORT bool DismissVirtualKeyboard();
 
 // Returns true if the machine is enrolled to a domain.
 BASE_EXPORT bool IsEnrolledToDomain();
 
+// Marker added to certain WM_MOUSEMOVE messages.
+#define SPECIAL_MOUSEMOVE_NOT_TO_BE_TRACKED 0xbeef
+
 }  // namespace win
 }  // namespace base
 
 #endif  // BASE_WIN_WIN_UTIL_H_