Convert DeviceManagerDelegate to PermissionProvider mojo interface.

chrome/browser/usb/web_usb_permission_provider.cc

+// Copyright 2015 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/usb/web_usb_permission_provider.h"
+#include "content/public/browser/browser_thread.h"
+
+namespace chrome {
+
+// static
+void WebUSBPermissionProvider::Create(
+    content::RenderFrameHost* render_frame_host,
+    mojo::InterfaceRequest<PermissionProvider> request) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));

[Lei Zhang, 2015/09/05 00:24:20]

DCHECK_CURRENTLY_ON()

[Reilly Grant (use Gerrit), 2015/09/05 00:56:25]

Done.

+  DCHECK(render_frame_host);
+
+  // The created object is strongly bound to (and owned by) the pipe.
+  new WebUSBPermissionProvider(render_frame_host, request.Pass());
+}
+
+WebUSBPermissionProvider::WebUSBPermissionProvider(
+    content::RenderFrameHost* render_frame_host,
+    mojo::InterfaceRequest<PermissionProvider> request)
+    : binding_(this, request.Pass()),
+      render_frame_host_(render_frame_host) {}
+
+WebUSBPermissionProvider::~WebUSBPermissionProvider() {}
+
+void WebUSBPermissionProvider::HasDevicePermission(
+    mojo::Array<mojo::String> requested_guids,
+    const HasDevicePermissionCallback& callback) {
+  // TODO(reillyg): Look up permissions granted to the render frame host's
+  // current origin in the render frame process's browser context.
+  ignore_result(render_frame_host_);

[Lei Zhang, 2015/09/05 00:24:20]

What's this suppose to do?

[Reilly Grant (use Gerrit), 2015/09/05 00:56:25]

It silences a warning that the private member is unused.

[Lei Zhang, 2015/09/05 01:18:14]

Add a comment?

// Make a dummy reference to the variable for now to make the compiler happy.

[Reilly Grant (use Gerrit), 2015/09/05 01:56:46]

Done.

+  mojo::Array<mojo::String> allowed_guids(0);
+  callback.Run(allowed_guids.Pass());
+}
+
+}  // namespace chrome