Plumb Push API permission request through Blink using Frame.

Source/modules/push_messaging/PushPermissionClient.cpp

+// Copyright 2014 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 "config.h"
+#include "modules/push_messaging/PushPermissionClient.h"
+
+#include "core/dom/Document.h"
+#include "core/dom/ExecutionContext.h"
+#include "core/frame/LocalFrame.h"
+
+namespace blink {
+
+const char* PushPermissionClient::supplementName()
+{
+    return "PushPermissionClient";
+}
+
+PushPermissionClient* PushPermissionClient::from(ExecutionContext* context)
+{
+    if (!context->isDocument())

[Mike West, 2014/11/06 14:21:20]

Hrm. Isn't this sort of thing supposed to work inside workers?

[Michael van Ouwerkerk, 2014/11/06 14:59:46]

No, this is exactly the part that cannot work inside a service worker, because
there is no direct association with a frame. PushPermissionClient is a
supplement of LocalFrame. A frame is required to display the permission request
ui (an infobar) to the user.

+        return 0;
+
+    const Document* document = toDocument(context);
+    ASSERT(document->frame());
+
+    if (!document->frame()->isLocalFrame())

[Mike West, 2014/11/06 14:21:20]

Can you add a FIXME to support RemoteFrames? (Or potentially assert that this
isn't a remote frame; it's not clear that we'd actually want to support that
case).

[Michael van Ouwerkerk, 2014/11/06 14:59:46]

Isn't returning null sufficient? I'm not sure we'd want to support this with
remote frames.

+        return 0;
+
+    return static_cast<PushPermissionClient*>(WillBeHeapSupplement<LocalFrame>::from(document->frame(), supplementName()));
+}
+
+void providePushPermissionClientTo(LocalFrame& frame, PassOwnPtrWillBeRawPtr<PushPermissionClient> client)
+{
+    frame.provideSupplement(PushPermissionClient::supplementName(), client);
+}
+
+}