AU: Remove obsolete postinst --postcommit call.

BUG=6251
TEST=unit test, tested update on device

Change-Id: Ib44b4698cab5fa1f2d0b5afd04dca500c8dbe84c

Review URL: http://codereview.chromium.org/4679003
diff --git a/update_attempter_unittest.cc b/update_attempter_unittest.cc
index eec342d..53ffc89 100644
--- a/update_attempter_unittest.cc
+++ b/update_attempter_unittest.cc
@@ -85,7 +85,7 @@
   FilesystemCopierAction filesystem_copier_action(false);
   EXPECT_EQ(kActionCodeFilesystemCopierError,
             GetErrorCodeForAction(&filesystem_copier_action, kActionCodeError));
-  PostinstallRunnerAction postinstall_runner_action(true);
+  PostinstallRunnerAction postinstall_runner_action;
   EXPECT_EQ(kActionCodePostinstallRunnerError,
             GetErrorCodeForAction(&postinstall_runner_action,
                                   kActionCodeError));
@@ -171,7 +171,6 @@
     DownloadAction::StaticType(),
     OmahaRequestAction::StaticType(),
     PostinstallRunnerAction::StaticType(),
-    PostinstallRunnerAction::StaticType(),
     OmahaRequestAction::StaticType()
   };
   for (size_t i = 0; i < arraysize(kActionTypes); ++i) {