Implement the feedbackPrivate API.

chrome/renderer/extensions/feedback_private_custom_bindings.cc

Index: chrome/renderer/extensions/feedback_private_custom_bindings.cc
diff --git a/chrome/renderer/extensions/feedback_private_custom_bindings.cc b/chrome/renderer/extensions/feedback_private_custom_bindings.cc
new file mode 100644
index 0000000000000000000000000000000000000000..bc84f5e58d8a4be913f0d879f202e1804207d264
--- /dev/null
+++ b/chrome/renderer/extensions/feedback_private_custom_bindings.cc
@@ -0,0 +1,30 @@
+// Copyright (c) 2012 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/renderer/extensions/feedback_private_custom_bindings.h"
+
+#include "base/bind.h"
+#include "third_party/WebKit/public/platform/WebCString.h"
+#include "third_party/WebKit/public/platform/WebURL.h"
+#include "third_party/WebKit/public/web/WebBlob.h"
+
+namespace {
+
+void GetBlobUrl(const v8::FunctionCallbackInfo<v8::Value> &args) {
+  DCHECK(args.Length() == 1);
+  WebKit::WebBlob blob = WebKit::WebBlob::fromV8Value(args[0]);
+  args.GetReturnValue().Set(v8::String::New(blob.url().spec().data()));

[kinuko, 2013/06/18 06:00:56]

Drive-by comment. WebBlob::url() returns Blob's internal URL, which is
automatically unregistered when the Blob's reference is GC'ed.  We have a
standard way to get a Blob URL in JS layer
(http://www.w3.org/TR/FileAPI/#dfn-createObjectURL) which actually adds a
reference to the Blob so that the Blob and its data is alive until we do call
revokeObjectURL.

Is there a reason we don't use the standard way to get a 'public' Blob URL in
feedback_private_custom_bindings.js but use this V8 wrapper code?  Are we sure
the blob reference is around when we use the URL?

+}
+
+}  // namespace
+
+namespace extensions {
+
+FeedbackPrivateCustomBindings::FeedbackPrivateCustomBindings(
+    Dispatcher* dispatcher,
+    ChromeV8Context* context) : ChromeV8Extension(dispatcher, context) {
+  RouteFunction("GetBlobUrl", base::Bind(&GetBlobUrl));
+}
+
+}  // namespace extensions