Use MAKEPOINTS instead of GET_X/Y_LPARAM to reduce a dependency on ATL....

base/gfx/point.h

Index: base/gfx/point.h
===================================================================
--- base/gfx/point.h	(revision 25700)
+++ base/gfx/point.h	(working copy)
@@ -10,6 +10,7 @@
 #include <iosfwd>
 
 #if defined(OS_WIN)
+typedef unsigned long DWORD;
 typedef struct tagPOINT POINT;
 #elif defined(OS_MACOSX)
 #include <ApplicationServices/ApplicationServices.h>
@@ -25,6 +26,10 @@
   Point();
   Point(int x, int y);
 #if defined(OS_WIN)
+  // |point| is a DWORD value that contains a coordinate.  The x-coordinate is
+  // the low-order short and the y-coordinate is the high-order short.  This
+  // value is commonly acquired from GetMessagePos/GetCursorPos.
+  explicit Point(DWORD point);
   explicit Point(const POINT& point);
   Point& operator=(const POINT& point);
 #elif defined(OS_MACOSX)
@@ -72,4 +77,4 @@
 
 std::ostream& operator<<(std::ostream& out, const gfx::Point& p);
 
-#endif // BASE_GFX_POINT_H__
+#endif  // BASE_GFX_POINT_H__