Improve Mojo permission service and chrome::PermissionManager observing.

This is fixing two bugs:
- mojo callbacks were not always run, which is now required.
- the service was not always unsubscribing from the PermissionManager,
  keeping stalled subscriptions alive.

BUG=430238, 437770

Review URL: https://codereview.chromium.org/1054653002

Cr-Commit-Position: refs/heads/master@{#323368}

1 files changed, 11 insertions, 1 deletions

diff --git a/chrome/browser/permissions/permission_manager.cc b/chrome/browser/permissions/permission_manager.cc
index 44f281a..217ec7f 100644
--- a/chrome/browser/permissions/permission_manager.cc
+++ b/chrome/browser/permissions/permission_manager.cc
@@ -207,6 +207,8 @@ void PermissionManager::OnContentSettingChanged(
     const ContentSettingsPattern& secondary_pattern,
     ContentSettingsType content_type,
     std::string resource_identifier) {
+  std::list<base::Closure> callbacks;
+
   for (SubscriptionsMap::iterator iter(&subscriptions_);
        !iter.IsAtEnd(); iter.Advance()) {
     Subscription* subscription = iter.GetCurrentValue();
@@ -230,6 +232,14 @@ void PermissionManager::OnContentSettingChanged(
       continue;
 
     subscription->current_value = new_value;
-    subscription->callback.Run(ContentSettingToPermissionStatus(new_value));
+
+    // Add the callback to |callbacks| which will be run after the loop to
+    // prevent re-entrance issues.
+    callbacks.push_back(
+        base::Bind(subscription->callback,
+                   ContentSettingToPermissionStatus(new_value)));
   }
+
+  for (const auto& callback : callbacks)
+    callback.Run();
 }