Preliminary support for GSSAPI (Linux and Mac OS X).

net/net.gyp

Index: net/net.gyp
diff --git a/net/net.gyp b/net/net.gyp
index 5be0beef4f7dbcfa9c9ff390360655341731cfa2..35616252dce9aa849a723c853363f7bbf2eee43e 100644
--- a/net/net.gyp
+++ b/net/net.gyp
@@ -327,6 +327,8 @@
         'http/http_auth_filter.cc',
         'http/http_auth_filter.h',
         'http/http_auth_filter_win.h',
+        'http/http_auth_gssapi_posix.cc',
+        'http/http_auth_gssapi_posix.h',
         'http/http_auth_handler.cc',
         'http/http_auth_handler.h',
         'http/http_auth_handler_basic.cc',
@@ -683,6 +685,7 @@
         'http/http_alternate_protocols_unittest.cc',
         'http/http_auth_cache_unittest.cc',
         'http/http_auth_filter_unittest.cc',
+        'http/http_auth_gssapi_posix_unittest.cc',
         'http/http_auth_handler_basic_unittest.cc',
         'http/http_auth_handler_digest_unittest.cc',
         'http/http_auth_handler_factory_unittest.cc',
@@ -763,6 +766,9 @@
           ],
         }],
         [ 'OS == "win"', {
+            'sources!': [
+              'http/http_auth_gssapi_posix_unittest.cc',
+            ],
             # This is needed to trigger the dll copy step on windows.
             # TODO(mark): Specifying this here shouldn't be necessary.
             'dependencies': [