Add support for the 'webview_android' policy configuration

grit/format/policy_templates/writers/template_writer.py

 #!/usr/bin/env python
 # 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.
 
 
 class TemplateWriter(object):
   '''Abstract base class for writing policy templates in various formats.
   The methods of this class will be called by PolicyTemplateGenerator.
   '''
@@ skipping 73 matching lines @@
     return False
 
   def CanBeRecommended(self, policy):
     '''Checks if the given policy can be recommended.'''
     return policy.get('features', {}).get('can_be_recommended', False)
 
   def CanBeMandatory(self, policy):
     '''Checks if the given policy can be mandatory.'''
     return policy.get('features', {}).get('can_be_mandatory', True)
 
-  def IsPolicySupportedOnPlatform(self, policy, platform):
+  def IsPolicySupportedOnPlatform(self, policy, platform, product=None):
     '''Checks if |policy| is supported on |platform|.
 
     Args:
       policy: The dictionary of the policy.
       platform: The platform to check; one of 'win', 'mac', 'linux' or
         'chrome_os'.
     '''
-    is_supported = lambda x: platform in x['platforms']

[Nico, 2015/11/02 16:41:10]

This returns a bool…

+
+    def is_supported(supported_on):
+      if not platform in supported_on['platforms']:

[Nico, 2015/11/02 16:41:10]

nit: `platform not in` instead of `not platform in`

[dgn, 2015/11/02 18:19:50]

Acknowledged.

+        return None
+      if product and not product in supported_on['product']:

[Nico, 2015/11/02 16:41:10]

same nit

[dgn, 2015/11/02 18:19:50]

Acknowledged.

+        return None
+      return supported_on

[Nico, 2015/11/02 16:41:10]

…but this returns an object. Since it's used with filter() which talks about
boolean values, I think returning False and True instead of None and
supported_on is easier to understand.

Is this function body equivalent to

  return platform in so[] and (!product or product in so[])

? (Technically, that also needs an `and bool(supported_on)`, but you already use
`in supported_on`, so if supported_on was None or empty that'd already fail)

[dgn, 2015/11/02 18:19:50]

Done.

+
     return any(filter(is_supported, policy['supported_on']))
 
   def _GetChromiumVersionString(self):
     '''Returns the Chromium version string stored in the environment variable
     version (if it is set).
 
     Returns: The Chromium version string or None if it has not been set.'''
 
     if 'version' in self.config:
       return self.config['version']
@@ skipping 196 matching lines @@
     '''
     is_group = policy['type'] == 'group'
     if is_group:
       # Groups are sorted by caption.
       str_key = policy['caption']
     else:
       # Regular policies are sorted by name.
       str_key = policy['name']
     # Groups come before regular policies.
     return (not is_group, str_key)