mac: use png otr icon asset instead of pdf

chrome/chrome_dll.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.
 {
   'conditions': [
     ['OS=="mac" or OS=="win"', {
       'targets': [
         {
           'target_name': 'chrome_dll',
           'type': 'none',
@@ skipping 268 matching lines @@
                 'app/nibs/TaskManager.xib',
                 'app/nibs/Toolbar.xib',
                 'app/nibs/WrenchMenu.xib',
                 'app/theme/balloon_wrench.pdf',
                 'app/theme/chevron.pdf',
                 'app/theme/find_next_Template.pdf',
                 'app/theme/find_prev_Template.pdf',
                 'app/theme/menu_hierarchy_arrow.pdf',
                 'app/theme/menu_overflow_down.pdf',
                 'app/theme/menu_overflow_up.pdf',
-                'app/theme/otr_icon.pdf',
                 'browser/mac/install.sh',
                 '<(SHARED_INTERMEDIATE_DIR)/repack/chrome.pak',
                 '<(SHARED_INTERMEDIATE_DIR)/repack/chrome_100_percent.pak',
                 '<(SHARED_INTERMEDIATE_DIR)/repack/resources.pak',
                 '<!@pymod_do_main(repack_locales -o -p <(OS) -g <(grit_out_dir) -s <(SHARED_INTERMEDIATE_DIR) -x <(SHARED_INTERMEDIATE_DIR) <(locales))',
                 # Note: pseudo_locales are generated via the packed_resources
                 # dependency but not copied to the final target.  See
                 # common.gypi for more info.
               ],
               'mac_bundle_resources!': [
@@ skipping 235 matching lines @@
                   ],
                 }],
               ],  # conditions
             }],  # OS=="mac"
           ],  # conditions
         },  # target chrome_dll
       ],  # targets
     }],  # OS=="mac" or OS=="win"
   ],
 }