Mojom interface for Preferences

services/preferences/public/interfaces/preferences.mojom

Index: services/preferences/public/interfaces/preferences.mojom
diff --git a/services/preferences/public/interfaces/preferences.mojom b/services/preferences/public/interfaces/preferences.mojom
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index 0000000000000000000000000000000000000000..4c31e4b76f753e580f731fbe84be2ea5b0beea3f
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@@ -0,0 +1,20 @@
+// Copyright 2016 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.
+
+module prefs.mojom;
+
+import "mojo/common/common_custom_types.mojom";
+
+// Used to subscribe to preference changes within PreferenceManager. After
+// requesting to observe, the current values for all requested keys are sent.
+interface PreferenceObserver {

[James Cook, 2016/10/11 17:08:29]

drive-by naming question: Is there any particular reason that the directory is
"preference*s*", the interfaces are "preference", and the methods are
"preference*s*" again? It seems inconsistent.

[jonross, 2016/10/11 22:05:13]

Nope, just drift from when this was in the components/prefs/ dir, and there was
a Preference struct here.

For consistency I'll update these interfaces to "preferences"

[jonross, 2016/10/17 13:40:07]

Done.

+  OnPreferencesChanged(mojo.common.mojom.DictionaryValue preferences);
+};
+
+// Manages actual read/write of preference data. Accepts observers who subscribe
+// to preferences, notifying them of changes.
+interface PreferenceManager {
+  AddObserver(array<string> preferences, PreferenceObserver client);
+  SetPreferences(mojo.common.mojom.DictionaryValue preferences);
+};