Remove code for Mac and Linux virtual print drivers.

cloud_print/virtual_driver/posix/install_cloud_print_driver_mac.mm

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#import <ApplicationServices/ApplicationServices.h>
-#import <Foundation/NSAutoreleasePool.h>
-
-#include "cloud_print/virtual_driver/posix/installer_util_mac.h"
-
-const AEEventClass  kAECloudPrintInstallClass= 'GCPi';
-
-// Installer for Virtual Driver on Mac. Sends an Apple Event to
-// Chrome, launching it if necessary. The Apple Event registers
-// the virtual driver with the service process.
-int main() {
-  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
-  cloud_print::sendServiceProcessEvent(kAECloudPrintInstallClass);
-  [pool release];
-  return 0;
-}