Use generated shim headers for zlib.

skia/config/SkUserConfig.h

Index: skia/config/SkUserConfig.h
diff --git a/skia/config/SkUserConfig.h b/skia/config/SkUserConfig.h
index e09dd4b10ce6ebd248ab46bfdf4f5ebb5fccec59..a0cb64f941cead079b8134a2a223437debb39834 100644
--- a/skia/config/SkUserConfig.h
+++ b/skia/config/SkUserConfig.h
@@ -110,11 +110,7 @@
     include path.
  */
 //#define SK_ZLIB_INCLUDE <zlib.h>
-#if defined(USE_SYSTEM_ZLIB)
-#define SK_ZLIB_INCLUDE <zlib.h>
-#else
 #define SK_ZLIB_INCLUDE "third_party/zlib/zlib.h"

[Mark Mentovai, 2012/12/18 19:48:17]

#include MACRO is usually hard on preprocessors and breaks optimizations that
certain tools that try to speed things up try to use (like distcc-pump and other
things that do a “light” preprocessing, maybe goma too). If this is not
absolutely necessary now, we should just switch to #including at this path
directly.

[Paweł Hajdan Jr., 2012/12/18 20:57:41]

This is some skia mess, see e.g. third_party/skia/gyp/zlib.gyp . Changing this
now would make the landing pretty risky.

I'm fine with adding a TODO and doing that later. However, that would make us
use shim headers at least on iOS. That's fine for me, but some people might not
like it.

-#endif
 
 /*  Define this to allow PDF scalars above 32k.  The PDF/A spec doesn't allow
     them, but modern PDF interpreters should handle them just fine.