Remove showModalDialog (Chrome side)

components/policy/resources/policy_templates.json

 {
 # policy_templates.json - Metafile for policy templates
 #
 # The content of this file is evaluated as a Python expression.
 #
 # This file is used as input to generate the following policy templates:
 # ADM, ADMX+ADML, MCX/plist and html documentation.
 #
 # Policy templates are user interface definitions or documents about the
 # policies that can be used to configure Chrome. Each policy is a name-value
@@ skipping 6918 matching lines @@
           ],
         },
       },
       'items': [
         {
           'name': 'ShowModalDialog',
           'value': 'ShowModalDialog_EffectiveUntil20150430',
           'caption': '''Enable ShowModalDialog API through 2015.04.30''',
         }
       ],
-      'supported_on': ['chrome.*:37-', 'chrome_os:37-', 'android:37-'],
+      'supported_on': ['chrome.*:37-42', 'chrome_os:37-42', 'android:37-42'],

[Andrew T Wilson (Slow), 2015/02/27 09:45:36]

I actually think this is incorrect - what you are saying here is that
EnableDeprecatedWebPlatformFeatures is only supported up to chrome 42, but the
policy itself is supported, just not the ShowModalDialog item.

I'd actually just leave this file unchanged. It's OK - at some future point we
can remove the mention of ShowModalDialog, but I think we need to have *some*
values in the 'items' attribute above, so for now just leave it here.

       'features': {
         'dynamic_refresh': True,
         'per_profile': True,
       },
       'example_value': ['ShowModalDialog_EffectiveUntil20150430'],
       'id': 270,
       'caption': '''Enable deprecated web platform features for a limited time''',
       'desc': '''Specify a list of deprecated web platform features to re-enable temporarily.
 
       This policy gives administrators the ability to re-enable deprecated web platform features for a limited time. Features are identified by a string tag and the features corresponding to the tags included in the list specified by this policy will get re-enabled.
@@ skipping 376 matching lines @@
       'desc': '''Text appended in parentheses next to the policies top-level container to indicate that those policies are of the Recommended level''',
       'text': 'Default Settings (users can override)',
     },
     'doc_complex_policies_on_windows': {
       'desc': '''Text pointing the user to a help article for complex policies on Windows''',
       'text': '''encoded as a JSON string, for details see <ph name="COMPLEX_POLICIES_URL">http://www.chromium.org/administrators/complex-policies-on-windows<ex>http://www.chromium.org/administrators/complex-policies-on-windows</ex></ph>''',
     },
   },
   'placeholders': [],
 }