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

include/utils/win/SkIStream.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.
  */
 
 
 #ifndef SkIStream_DEFINED
 #define SkIStream_DEFINED
 
 #define WIN32_LEAN_AND_MEAN
-#include <Windows.h>
+#include <windows.h>
 #include <ole2.h>
 
 class SkStream;
 class SkWStream;
 
 /**
  * A bare IStream implementation which properly reference counts
  * but returns E_NOTIMPL for all ISequentialStream and IStream methods.
  */
 class SkBaseIStream : public IStream {
@@ skipping 97 matching lines @@
                                           , ULONG cb
                                           , ULONG* pcbWritten);
 
     virtual HRESULT STDMETHODCALLTYPE Commit(DWORD);
 
     virtual HRESULT STDMETHODCALLTYPE Stat(STATSTG* pStatstg
                                          , DWORD grfStatFlag);
 };
 
 #endif