[Web Payments] Initial plumb of Payment Request dialog

chrome/browser/payments/payment_request_impl.cc

+// Copyright 2016 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/payments/payment_request_impl.h"
+
+#include <set>
+
+#include "base/lazy_instance.h"
+#include "base/synchronization/lock.h"
+#include "chrome/browser/payments/ui/payment_request_dialog.h"
+#include "components/web_modal/web_contents_modal_dialog_host.h"
+#include "components/web_modal/web_contents_modal_dialog_manager.h"
+#include "components/web_modal/web_contents_modal_dialog_manager_delegate.h"
+#include "content/public/browser/web_contents.h"
+
+namespace {
+
+class PaymentRequestFactory {
+ public:
+  bool AssignPaymentRequest(
+      content::WebContents* web_contents,
+      mojo::InterfaceRequest<payments::mojom::PaymentRequest> request) {
+    mu_.Acquire();
+    if (set_.find(web_contents) == set_.end()) {

[Lei Zhang, 2016/11/15 19:20:47]

You can use base::ContainsKey() if that feels more readable.

[Kevin Bailey, 2016/11/15 20:33:55]

Not for me, but happy to follow Rouslan's preference.

[please use gerrit instead, 2016/11/15 20:38:07]

I prefer what you have written.

+      std::unique_ptr<payments::PaymentRequestImpl> p(
+          new payments::PaymentRequestImpl(web_contents, std::move(request)));

[Lei Zhang, 2016/11/15 19:20:47]

base::MakeUnique?

[Kevin Bailey, 2016/11/15 20:33:55]

Sorry, obsolete.

+      set_.insert(web_contents);
+      mu_.Release();
+      return true;
+    } else {

[Lei Zhang, 2016/11/15 19:20:47]

No need for else after a return.

[Kevin Bailey, 2016/11/15 20:33:55]

No harm in making the "either or" behavior more obvious either.
Done.

+      mu_.Release();
+      return false;
+    }
+  }
+
+  void UnassignPaymentRequest(content::WebContents* web_contents) {
+    mu_.Acquire();
+    set_.erase(web_contents);
+    mu_.Release();
+  }
+
+ private:
+  base::Lock mu_;

[Lei Zhang, 2016/11/15 19:20:47]

This is going to protect against thread-safe access? What threads call
(Un)AssignPaymentRequest() ?

[Kevin Bailey, 2016/11/15 19:26:35]

This comes directly from our conversation about multiple frames trying to open a
dialog.

[Lei Zhang, 2016/11/15 19:30:57]

When multiple frames try to communicate with the browser, AFAIK the browser
handles everything on the UI thread, so there's no racing. WebContents and many
other content/ classes all live on the UI thread too.

[Kevin Bailey, 2016/11/15 20:33:55]

I got rid of the lock, but if you're saying that there may be multiple
simultaneous WebContents (that a set<> is needed here), then another off-line
discussion may be in order.

[please use gerrit instead, 2016/11/15 20:41:04]

All WebContents objects live in the single browser process in the single UI
thread. Locks are only useful for the multi-process and multi-thread situations.

+  std::set<content::WebContents*> set_;
+};
+
+base::LazyInstance<PaymentRequestFactory> payment_request_factory;
+
+}  // namespace
+
+namespace payments {
+
+PaymentRequestImpl::PaymentRequestImpl(
+    content::WebContents* web_contents,
+    mojo::InterfaceRequest<payments::mojom::PaymentRequest> request)
+    : web_contents_(web_contents), binding_(this, std::move(request)) {}
+
+PaymentRequestImpl::~PaymentRequestImpl() {
+  payment_request_factory.Get().UnassignPaymentRequest(web_contents_);
+}
+
+void PaymentRequestImpl::Init(
+    payments::mojom::PaymentRequestClientPtr client,
+    std::vector<payments::mojom::PaymentMethodDataPtr> methodData,
+    payments::mojom::PaymentDetailsPtr details,
+    payments::mojom::PaymentOptionsPtr options) {
+  views::DialogDelegate::CreateDialogWidget(
+      new PaymentRequestDialog(std::move(client)), nullptr,
+      web_modal::WebContentsModalDialogManager::FromWebContents(web_contents_)
+          ->delegate()
+          ->GetWebContentsModalDialogHost()
+          ->GetHostView())
+      ->Show();
+}
+
+}  // namespace payments
+
+void CreatePaymentRequestHandler(
+    content::WebContents* web_contents,
+    mojo::InterfaceRequest<payments::mojom::PaymentRequest> request) {
+  payment_request_factory.Get().AssignPaymentRequest(web_contents,
+                                                     std::move(request));
+}