Have content_browser depend on printing only if not on iOS.

content/content_browser.gypi

 # Copyright (c) 2012 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.
 
 {
   'dependencies': [
     'browser/speech/proto/speech_proto.gyp:speech_proto',
     '../base/base.gyp:base_static',
     '../crypto/crypto.gyp:crypto',
     '../google_apis/google_apis.gyp:google_apis',
-    '../printing/printing.gyp:printing',
     '../net/net.gyp:net',
     '../skia/skia.gyp:skia',
     '../third_party/zlib/zlib.gyp:zlib',
     '../ui/ui.gyp:ui',
     '../ui/ui.gyp:ui_resources',
   ],
   'include_dirs': [
     '..',
     '<(INTERMEDIATE_DIR)',
   ],
@@ skipping 851 matching lines @@
         ['include', '^public/browser/notification_registrar\\.cc$'],
         ['include', '^public/browser/speech_recognition_'],
         ['include', '^browser/browser_context\\.cc$'],
         ['include', '^browser/notification_service_impl\\.cc$'],
       ],
     }, {  # OS!="ios"
       'dependencies': [
         'browser/debugger/devtools_resources.gyp:devtools_resources',
         '../net/net.gyp:http_server',
         '../ppapi/ppapi_internal.gyp:ppapi_ipc',
+        '../printing/printing.gyp:printing',
         '<(webkit_src_dir)/Source/WebKit/chromium/WebKit.gyp:webkit',
         '../ui/surface/surface.gyp:surface',
         '../webkit/support/webkit_support.gyp:dom_storage',
         '../webkit/support/webkit_support.gyp:webkit_resources',
         '../webkit/support/webkit_support.gyp:webkit_strings',
       ],
     }],
     ['OS!="mac" and OS!="ios"', {
       'dependencies': [
         '../sandbox/sandbox.gyp:sandbox',
@@ skipping 176 matching lines @@
         ['exclude', '^browser/renderer_host/java/'],
       ],
     }],
     ['input_speech==0', {
       'sources/': [
         ['exclude', '^browser/speech/'],
       ],
     }],
   ],
 }