Implement Permissions.query() and static PermissionStatus.

public/platform/Platform.h

Index: public/platform/Platform.h
diff --git a/public/platform/Platform.h b/public/platform/Platform.h
index 562aa1cc9017ff92c597bc1b64e3888c913f8974..13e2cf3d3e30a9711b5a9c4178431178543f7204 100644
--- a/public/platform/Platform.h
+++ b/public/platform/Platform.h
@@ -86,6 +86,7 @@ class WebMessagePortChannel;
 class WebMimeRegistry;
 class WebNavigatorConnectProvider;
 class WebNotificationManager;
+class WebPermissionClient;
 class WebPluginListBuilder;
 class WebPrescientNetworking;
 class WebPublicSuffixList;
@@ -659,6 +660,11 @@ public:
 
     virtual WebNavigatorConnectProvider* navigatorConnectProvider() { return 0; }
 
+    // Permissions --------------------------------------------------------
+
+    virtual WebPermissionClient* permissionClient() { return 0; }
+
+
 protected:
     BLINK_PLATFORM_EXPORT Platform();
     virtual ~Platform() { }