fltk: fix Mountain Lion build.

Fixes Homebrew/homebrew#13649, fixes Homebrew/homebrew#13887.

Formula/fltk.rb

@@ -19,8 +19,66 @@ class Fltk < Formula
     cause "http://llvm.org/bugs/show_bug.cgi?id=10338"
   end
 
+  # Fix Mountain Lion build.
+  # http://www.fltk.org/str.php?L2864
+  # Committed upstream as r9649
+  def patches
+    { :p0 => DATA }
+  end
+
   def install
     system "./configure", "--prefix=#{prefix}", "--enable-threads"
     system "make install"
   end
 end
+
+__END__
+Index: src/filename_list.cxx
+===================================================================
+--- src/filename_list.cxx	(revision 9648)
++++ src/filename_list.cxx	(revision 9649)
+@@ -22,7 +22,9 @@
+ #include <FL/fl_utf8.h>
+ #include "flstring.h"
+ #include <stdlib.h>
+-
++#ifdef __APPLE__
++#include <FL/x.H>
++#endif
+
+ extern "C" {
+ #ifndef HAVE_SCANDIR
+@@ -95,7 +97,7 @@
+ #ifndef HAVE_SCANDIR
+   // This version is when we define our own scandir
+   int n = fl_scandir(dirloc, list, 0, sort);
+-#elif defined(HAVE_SCANDIR_POSIX) && !defined(__APPLE__)
++#elif defined(HAVE_SCANDIR_POSIX)
+   // POSIX (2008) defines the comparison function like this:
+   int n = scandir(dirloc, list, 0, (int(*)(const dirent **, const dirent **))sort);
+ #elif defined(__osf__)
+Index: FL/mac.H
+===================================================================
+--- FL/mac.H	(revision 9648)
++++ FL/mac.H	(revision 9649)
+@@ -149,6 +149,21 @@
+ #ifndef MAC_OS_X_VERSION_10_6
+ #define MAC_OS_X_VERSION_10_6 1060
+ #endif
++#ifndef MAC_OS_X_VERSION_10_7
++#define MAC_OS_X_VERSION_10_7 1070
++#endif
++#ifndef MAC_OS_X_VERSION_10_8
++#define MAC_OS_X_VERSION_10_8 1080
++#endif
++
++#if defined(FL_LIBRARY) || defined(FL_INTERNALS)
++#ifdef HAVE_SCANDIR_POSIX
++#undef HAVE_SCANDIR_POSIX
++#endif
++#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_8
++#define HAVE_SCANDIR_POSIX 1
++#endif
++#endif // FL_LIBRARY || FL_INTERNALS
+
+ typedef CGImageRef Fl_Bitmask;