Use open-vcdiff for sdch compression on the Mac

net/base/filter.cc

Index: net/base/filter.cc
===================================================================
--- net/base/filter.cc	(revision 2604)
+++ net/base/filter.cc	(working copy)
@@ -7,8 +7,8 @@
 #include "base/string_util.h"
 #include "net/base/gzip_filter.h"
 #include "net/base/bzip2_filter.h"
-#if defined(OS_WIN)
-// TODO(port): restore when sdch works on non-Windows.
+#if defined(OS_WIN) || defined(OS_MACOSX)
+// TODO(port): remove #ifdef when sdch works on all platforms.
 #include "net/base/sdch_filter.h"
 #endif
 
@@ -85,8 +85,8 @@
   } else if (LowerCaseEqualsASCII(filter_type, kBZip2) ||
              LowerCaseEqualsASCII(filter_type, kXBZip2)) {
     type_id = FILTER_TYPE_BZIP2;
-#if defined(OS_WIN)
-    // TODO(port): restore when sdch works on non-Windows.
+#if defined(OS_WIN) || defined(OS_MACOSX)
+    // TODO(port): remove #ifdef when sdch works on all platforms.
   } else if (LowerCaseEqualsASCII(filter_type, kSdch)) {
     type_id = FILTER_TYPE_SDCH;
 #endif
@@ -116,8 +116,8 @@
       }
       break;
     }
-#if defined(OS_WIN)
-    // TODO(port): restore when sdch works on non-Windows.
+#if defined(OS_WIN) || defined(OS_MACOSX)
+    // TODO(port): remove #ifdef when sdch works on all platforms.
     case FILTER_TYPE_SDCH: {
       scoped_ptr<SdchFilter> sdch_filter(new SdchFilter());
       if (sdch_filter->InitBuffer(buffer_size)) {