Support "always allow" for runtime script execution

chrome/browser/extensions/permissions_updater.cc

 // 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.
 
 #include "chrome/browser/extensions/permissions_updater.h"
 
 #include "base/json/json_writer.h"
 #include "base/memory/ref_counted.h"
 #include "base/values.h"
 #include "chrome/browser/chrome_notification_types.h"
@@ skipping 49 matching lines @@
       PermissionsParser::GetOptionalPermissions(extension));
 
   // Make sure the active permissions contain no more than optional + default.
   scoped_refptr<PermissionSet> adjusted_active =
       PermissionSet::CreateIntersection(total_permissions, active_permissions);
 
   // Make sure the active permissions contain the default permissions.
   adjusted_active =
       PermissionSet::CreateUnion(required_permissions, adjusted_active);
 
+  // Re-add any active permissions that only match a single origin in order
+  // to persist "always run" script injection hosts.

[not at google - send to devlin, 2014/08/11 22:59:30]

Mention why they were filtered out in the first place.

[gpdavis, 2014/08/12 00:52:05]

Done.

[not at google - send to devlin, 2014/08/12 19:49:26]

The comment still doesn't work for me, but I think it's because this is actually
in the wrong place. See newer comment.

+  URLPatternSet single_origin_explicit;
+  URLPatternSet single_origin_scriptable;
+  for (URLPatternSet::const_iterator iter =
+           active_permissions->explicit_hosts().begin();
+       iter != active_permissions->explicit_hosts().end();
+       ++iter) {
+    if (iter->MatchesSingleOrigin())
+      single_origin_explicit.AddPattern(*iter);
+  }
+  for (URLPatternSet::const_iterator iter =
+           active_permissions->scriptable_hosts().begin();
+       iter != active_permissions->scriptable_hosts().end();
+       ++iter) {
+    if (iter->MatchesSingleOrigin())
+      single_origin_scriptable.AddPattern(*iter);
+  }
+

[not at google - send to devlin, 2014/08/11 22:59:30]

you could write this much more concisely if you had a FilterSingleOriginPatterns
method, such that you can call

adjusted_active = PermissionSet::CreateUnion(
    adjusted_active,
    new PermissionSet(APIPermissionSet(),
                      ManifestPermissionSet(),
                     
FilterSingleOriginPermissions(active_permissions->explicit_hosts()),
                     
FilterSingleOriginPermissions(active_permissions->scriptable_hosts());

formatting modulo git-cl format.

[gpdavis, 2014/08/12 00:52:05]

Done.

+  adjusted_active = PermissionSet::CreateUnion(
+      adjusted_active,
+      new PermissionSet(APIPermissionSet(),
+                        ManifestPermissionSet(),
+                        single_origin_explicit,
+                        single_origin_scriptable));
+
   return adjusted_active;
 }
 
 // Divvy up the |url patterns| between those we grant and those we do not. If
 // |withhold_permissions| is false (because the requisite feature is not
 // enabled), no permissions are withheld.
 void SegregateUrlPermissions(const URLPatternSet& url_patterns,
                              bool withhold_permissions,
                              URLPatternSet* granted,
                              URLPatternSet* withheld) {
@@ skipping 241 matching lines @@
             Profile::FromBrowserContext(host->GetBrowserContext()))) {
       host->Send(new ExtensionMsg_UpdatePermissions(params));
     }
   }
 
   // Trigger the onAdded and onRemoved events in the extension.
   DispatchEvent(extension->id(), event_name, changed);
 }
 
 }  // namespace extensions