Support Kerberos on Android

net/http/http_auth_gssapi_posix.h

Index: net/http/http_auth_gssapi_posix.h
diff --git a/net/http/http_auth_gssapi_posix.h b/net/http/http_auth_gssapi_posix.h
index ab967c96053fe3052ac8f70a199640c960da47ec..594f6690ab5b649d6143e7a89972899fcedcafe0 100644
--- a/net/http/http_auth_gssapi_posix.h
+++ b/net/http/http_auth_gssapi_posix.h
@@ -9,6 +9,7 @@
 
 #include "base/gtest_prod_util.h"
 #include "base/native_library.h"
+#include "net/base/completion_callback.h"
 #include "net/base/net_export.h"
 #include "net/http/http_auth.h"
 
@@ -248,6 +249,8 @@ class NET_EXPORT_PRIVATE HttpAuthGSSAPI {
   // Generates an authentication token.
   // The return value is an error code. If it's not |OK|, the value of
   // |*auth_token| is unspecified.
+  // The function may return |IO_PENDING|, and call |callback| on completion.
+  // |auth_token| must remain valid until the callback has been called.
   // |spn| is the Service Principal Name of the server that the token is
   // being generated for.
   // If this is the first round of a multiple round scheme, credentials are
@@ -255,7 +258,8 @@ class NET_EXPORT_PRIVATE HttpAuthGSSAPI {
   // credentials are used instead.
   int GenerateAuthToken(const AuthCredentials* credentials,
                         const std::string& spn,
-                        std::string* auth_token);
+                        std::string* auth_token,
+                        const CompletionCallback& callback);
 
   // Delegation is allowed on the Kerberos ticket. This allows certain servers
   // to act as the user, such as an IIS server retrieiving data from a