Use lowercase windows.h in includes to fix Windows cross compilation using mingw.

src/views/win/skia_win.cpp

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
-#include <Windows.h>
+#include <windows.h>
 #include <tchar.h>
 
 #include "SkApplication.h"
 
 #define MAX_LOADSTRING 100
 
 // Global Variables:
 HINSTANCE hInst;                            // current instance
 TCHAR szTitle[] = _T("SampleApp");          // The title bar text
 TCHAR szWindowClass[] = _T("SAMPLEAPP");    // the main window class name
@@ skipping 179 matching lines @@
     case WM_COMMAND:
         if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL)
         {
             EndDialog(hDlg, LOWORD(wParam));
             return (INT_PTR)TRUE;
         }
         break;
     }
     return (INT_PTR)FALSE;
 }