Split printing utility IPC messages into its own file.

chrome/chrome_utility.gypi

Index: chrome/chrome_utility.gypi
diff --git a/chrome/chrome_utility.gypi b/chrome/chrome_utility.gypi
index a5e1e44d7cb6fb7d8cbcd050ed9a56e9579d774b..d80f721551af44347aa42759008bd0effc8bab2d 100644
--- a/chrome/chrome_utility.gypi
+++ b/chrome/chrome_utility.gypi
@@ -71,6 +71,8 @@
         'utility/importer/nss_decryptor_win.h',
         'utility/importer/safari_importer.h',
         'utility/importer/safari_importer.mm',
+        'utility/local_discovery/service_discovery_message_handler.cc',
+        'utility/local_discovery/service_discovery_message_handler.h',
         'utility/media_galleries/image_metadata_extractor.cc',
         'utility/media_galleries/image_metadata_extractor.h',
         'utility/media_galleries/ipc_data_source.cc',
@@ -79,6 +81,8 @@
         'utility/media_galleries/itunes_pref_parser_win.h',
         'utility/media_galleries/media_metadata_parser.cc',
         'utility/media_galleries/media_metadata_parser.h',
+        'utility/printing_handler.cc',
+        'utility/printing_handler.h',
         'utility/profile_import_handler.cc',
         'utility/profile_import_handler.h',
         'utility/utility_message_handler.h',
@@ -133,17 +137,23 @@
             ['exclude', '^utility/profile_import_handler\.cc'],
           ],
         }],
-        ['enable_mdns == 1', {
-          'sources': [
-            'utility/local_discovery/service_discovery_message_handler.cc',
-            'utility/local_discovery/service_discovery_message_handler.h',
-          ]
-        }],
         ['OS!="win"', {
           'sources': [
             'utility/image_writer/image_writer_stub.cc',
           ]
         }],
+        ['enable_printing!=1', {
+          'sources!': [
+            'utility/printing_handler.cc',
+            'utility/printing_handler.h',
+          ]
+        }],
+        ['enable_mdns==0', {
+          'sources!': [
+            'utility/local_discovery/service_discovery_message_handler.cc',
+            'utility/local_discovery/service_discovery_message_handler.h',
+          ]
+        }],
       ],
       # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
       'msvs_disabled_warnings': [ 4267, ],