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

include/utils/SkWGL.h

 
 /*
  * 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 "SkRefCnt.h"
 
 #ifndef SkWGL_DEFINED
 #define SkWGL_DEFINED
 
 /**
  * Working with WGL extensions can be a pain. Among the reasons is that You must
  * have a GL context to get the proc addresses, but you want to use the procs to
  * create a context in the first place. So you have to create a dummy GL ctx to
  * get the proc addresses.
  *
  * This file helps by providing SkCreateWGLInterface(). It returns a struct of
  * function pointers that it initializes. It also has a helper function to query
  * for WGL extensions. It handles the fact that wglGetExtensionsString is itself
  * an extension.
  */
 
 #if !defined(WIN32_LEAN_AND_MEAN)
     #define WIN32_LEAN_AND_MEAN
     #define SK_LOCAL_LEAN_AND_MEAN
 #endif
-#include <Windows.h>
+#include <windows.h>
 #if defined(SK_LOCAL_LEAN_AND_MEAN)
     #undef WIN32_LEAN_AND_MEAN
     #undef SK_LOCAL_LEAN_AND_MEAN
 #endif
 
 #define SK_WGL_DRAW_TO_WINDOW                       0x2001
 #define SK_WGL_ACCELERATION                         0x2003
 #define SK_WGL_SUPPORT_OPENGL                       0x2010
 #define SK_WGL_DOUBLE_BUFFER                        0x2011
 #define SK_WGL_COLOR_BITS                           0x2014
@@ skipping 65 matching lines @@
 
 /**
  * Helper to create an OpenGL context for a DC using WGL. Configs with a sample count >= to
  * msaaSampleCount are preferred but if none is available then a context with a lower sample count
  * (including non-MSAA) will be created. If preferCoreProfile is true but a core profile cannot be
  * created then a compatible profile context will be created.
  */
 HGLRC SkCreateWGLContext(HDC dc, int msaaSampleCount, bool preferCoreProfile);
 
 #endif