Attempt at once-and-for-all fix for bug #2993 (Windows)

views/widget/widget_win.h

Index: views/widget/widget_win.h
===================================================================
--- views/widget/widget_win.h	(revision 20614)
+++ views/widget/widget_win.h	(working copy)
@@ -504,6 +504,9 @@
   void ProcessMouseMoved(const CPoint& point, UINT flags, bool is_nonclient);
   void ProcessMouseExited();
 
+  // Check for out-of-order mouse button releases
+  void CheckOutOfOrderMouseButtonRelease(int code);
+
   // Handles re-laying out content in response to a window size change.
   virtual void ChangeSize(UINT size_param, const CSize& size);
 
@@ -638,6 +641,18 @@
   int last_mouse_move_x_;
   int last_mouse_move_y_;
 
+  // Store whether the left and right mouse buttons are swapped in the Windows
+  // settings, and which virtual key code (VK_...) belongs to which button.
+  bool mouse_buttons_are_swapped_;
+  int left_button_code_;
+  int right_button_code_;
+
+  // keep track which buttons are currently pressed
+  int buttons_pressed_;
+
+  // Did we process a release button event out of order? (see ProcessMouseMoved)
+  int released_buttons_out_of_order_;
+
   // Instance of accessibility information and handling for MSAA root
   CComPtr<IAccessible> accessibility_root_;