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

While it doesn't matter on Windows, mingw on case-sensitive OSes uses all lower case filenames for platform include files. I found the problem in SkCondVar.h from Mozilla checkout of skia sources, but the patch contains a fix for the whole skia tree.

R=bungeman@google.com

Review URL: https://codereview.chromium.org/99173003

git-svn-id: http://skia.googlecode.com/svn/trunk/include@12461 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gpu/gl/SkNativeGLContext.h b/gpu/gl/SkNativeGLContext.h
index a18c443..7254de1 100644
--- a/gpu/gl/SkNativeGLContext.h
+++ b/gpu/gl/SkNativeGLContext.h
@@ -19,7 +19,7 @@
     #include <X11/Xlib.h>
     #include <GL/glx.h>
 #elif defined(SK_BUILD_FOR_WIN32)
-    #include <Windows.h>
+    #include <windows.h>
     #include <GL/GL.h>
 #endif
 
diff --git a/utils/SkCondVar.h b/utils/SkCondVar.h
index 15f16e6..861a2ab 100644
--- a/utils/SkCondVar.h
+++ b/utils/SkCondVar.h
@@ -11,7 +11,7 @@
 #ifdef SK_USE_POSIX_THREADS
 #include <pthread.h>
 #elif defined(SK_BUILD_FOR_WIN32)
-#include <Windows.h>
+#include <windows.h>
 #endif
 
 /**
diff --git a/utils/SkWGL.h b/utils/SkWGL.h
index 6803e03..5f630a1 100644
--- a/utils/SkWGL.h
+++ b/utils/SkWGL.h
@@ -27,7 +27,7 @@
     #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
diff --git a/utils/win/SkAutoCoInitialize.h b/utils/win/SkAutoCoInitialize.h
index 709fa6b..f671e68 100644
--- a/utils/win/SkAutoCoInitialize.h
+++ b/utils/win/SkAutoCoInitialize.h
@@ -11,7 +11,7 @@
 #define SkAutoCo_DEFINED
 
 #define WIN32_LEAN_AND_MEAN
-#include <Windows.h>
+#include <windows.h>
 #include "SkTemplates.h"
 
 /**
diff --git a/utils/win/SkIStream.h b/utils/win/SkIStream.h
index e4e045c..deb3f3b 100644
--- a/utils/win/SkIStream.h
+++ b/utils/win/SkIStream.h
@@ -11,7 +11,7 @@
 #define SkIStream_DEFINED
 
 #define WIN32_LEAN_AND_MEAN
-#include <Windows.h>
+#include <windows.h>
 #include <ole2.h>
 
 class SkStream;