Implement Web Restrictions in WebView.

components/supervised_user_error_page/supervised_user_gin_wrapper.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 "components/supervised_user_error_page/supervised_user_gin_wrapper.h"
+
+#include "base/strings/utf_string_conversions.h"
+#include "components/web_restrictions/browser/web_restrictions_client.h"
+#include "content/public/renderer/render_frame.h"
+#include "gin/handle.h"
+#include "gin/object_template_builder.h"
+#include "third_party/WebKit/public/web/WebKit.h"
+#include "third_party/WebKit/public/web/WebLocalFrame.h"
+
+namespace supervised_user_error_page {
+
+gin::WrapperInfo SupervisedUserGinWrapper::kWrapperInfo = {
+    gin::kEmbedderNativeGin};
+
+// static
+void SupervisedUserGinWrapper::Install(
+    content::RenderFrame* render_frame,
+    const std::string& url,
+    const web_restrictions::mojom::WebRestrictionsPtr&
+        web_restrictions_service) {
+  v8::Isolate* isolate = blink::mainThreadIsolate();
+  v8::HandleScope handle_scope(isolate);
+  v8::Local<v8::Context> context =
+      render_frame->GetWebFrame()->mainWorldScriptContext();
+  if (context.IsEmpty())
+    return;
+  v8::Context::Scope context_scope(context);
+  gin::Handle<SupervisedUserGinWrapper> controller = gin::CreateHandle(
+      isolate, new SupervisedUserGinWrapper(render_frame, url,
+                                            web_restrictions_service));
+  if (controller.IsEmpty())
+    return;
+  v8::Local<v8::Object> global = context->Global();
+  global->Set(gin::StringToV8(isolate, "webRestrictions"), controller.ToV8());
+}
+
+SupervisedUserGinWrapper::SupervisedUserGinWrapper(
+    content::RenderFrame* render_frame,
+    const std::string& url,
+    const web_restrictions::mojom::WebRestrictionsPtr& web_restrictions_service)
+    : content::RenderFrameObserver(render_frame),
+      url_(url),
+      web_restrictions_service_(web_restrictions_service),
+      weak_ptr_factory_(this) {}
+
+SupervisedUserGinWrapper::~SupervisedUserGinWrapper() {}
+
+bool SupervisedUserGinWrapper::RequestPermission() {
+  if (!render_frame())
+    return false;
+  web_restrictions_service_->RequestPermission(
+      url_, base::Bind(&SupervisedUserGinWrapper::OnAccessRequestAdded,
+                       weak_ptr_factory_.GetWeakPtr()));
+  render_frame()->GetWebFrame()->reload();
+  return true;
+}
+
+void SupervisedUserGinWrapper::OnAccessRequestAdded(bool success) {
+  VLOG(1) << "Sent access request for " << url_
+          << (success ? " successfully" : " unsuccessfully");
+  std::string jsFunc =
+      success ? "setRequestStatus(true);" : "setRequestStatus(false);";
+  render_frame()->ExecuteJavaScript(base::ASCIIToUTF16(jsFunc));

[jochen (gone - plz use gerrit), 2016/04/17 17:07:05]

please have the requestPermission method take a callback paramter you invoke
here instead of directly calling to a JS method.

see eg here for how to do this:
https://code.google.com/p/chromium/codesearch#chromium/src/components/test_ru...

[aberent, 2016/05/18 20:06:50]

Done. Please, however, review carefully. I have copied code from elsewhere
without fully understanding the V8 interface or gin, so, while it seems to work
I do not really know whether it is correct.

+}
+
+void SupervisedUserGinWrapper::OnDestruct() {
+  // Do nothing. Overrides version that deletes RenderFrameObserver.
+}
+
+gin::ObjectTemplateBuilder SupervisedUserGinWrapper::GetObjectTemplateBuilder(
+    v8::Isolate* isolate) {
+  return gin::Wrappable<SupervisedUserGinWrapper>::GetObjectTemplateBuilder(
+             isolate)
+      .SetMethod("requestPermission",
+                 &SupervisedUserGinWrapper::RequestPermission);
+}
+
+}  // namespace web_restrictions