webshare: Small refactor of WebShare (OnceCallback, const&, and alias)

chrome/browser/ui/views/webshare/webshare_target_picker_view.cc

 // Copyright 2017 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/ui/views/webshare/webshare_target_picker_view.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/ui/views/harmony/chrome_layout_provider.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/constrained_window/constrained_window_views.h"
@@ skipping 48 matching lines @@
                            ")");
 }
 
 void TargetPickerTableModel::SetObserver(ui::TableModelObserver* observer) {}
 
 namespace chrome {
 
 void ShowWebShareTargetPickerDialog(
     gfx::NativeWindow parent_window,
     const std::vector<std::pair<base::string16, GURL>>& targets,
-    const base::Callback<void(base::Optional<std::string>)>& callback) {
+    chrome::WebShareTargetPickerCallback callback) {
   constrained_window::CreateBrowserModalDialogViews(
-      new WebShareTargetPickerView(targets, callback), parent_window)
+      new WebShareTargetPickerView(targets, std::move(callback)), parent_window)
       ->Show();
 }
 
 }  // namespace chrome
 
 WebShareTargetPickerView::WebShareTargetPickerView(
     const std::vector<std::pair<base::string16, GURL>>& targets,
-    const base::Callback<void(base::Optional<std::string>)>& close_callback)
+    chrome::WebShareTargetPickerCallback close_callback)
     : targets_(targets),
       table_model_(base::MakeUnique<TargetPickerTableModel>(&targets_)),
-      close_callback_(close_callback) {
+      close_callback_(std::move(close_callback)) {
   const int panel_margin = ChromeLayoutProvider::Get()->GetDistanceMetric(
       DISTANCE_PANEL_CONTENT_MARGIN);
   views::BoxLayout* layout =
       new views::BoxLayout(views::BoxLayout::kVertical, panel_margin,
                            panel_margin, views::kRelatedControlVerticalSpacing);
   SetLayoutManager(layout);
 
   views::Label* overview_label = new views::Label(
       l10n_util::GetStringUTF16(IDS_WEBSHARE_TARGET_PICKER_LABEL));
   AddChildView(overview_label);
@@ skipping 29 matching lines @@
 ui::ModalType WebShareTargetPickerView::GetModalType() const {
   return ui::MODAL_TYPE_WINDOW;
 }
 
 base::string16 WebShareTargetPickerView::GetWindowTitle() const {
   return l10n_util::GetStringUTF16(IDS_WEBSHARE_TARGET_PICKER_TITLE);
 }
 
 bool WebShareTargetPickerView::Cancel() {
   if (!close_callback_.is_null())
-    close_callback_.Run(base::nullopt);
+    std::move(close_callback_).Run(base::nullopt);
 
   return true;
 }
 
 bool WebShareTargetPickerView::Accept() {
   if (!close_callback_.is_null()) {
     DCHECK(!table_->selection_model().empty());
-    close_callback_.Run(targets_[table_->FirstSelectedRow()].second.spec());
+    std::move(close_callback_)
+        .Run(targets_[table_->FirstSelectedRow()].second.spec());
   }
 
   return true;
 }
 
 base::string16 WebShareTargetPickerView::GetDialogButtonLabel(
     ui::DialogButton button) const {
   if (button == ui::DIALOG_BUTTON_OK)
     return l10n_util::GetStringUTF16(IDS_WEBSHARE_TARGET_PICKER_COMMIT);
 
   return views::DialogDelegateView::GetDialogButtonLabel(button);
 }
 
 bool WebShareTargetPickerView::IsDialogButtonEnabled(
     ui::DialogButton button) const {
   // User shouldn't select OK button if they haven't selected a target.
   if (button == ui::DIALOG_BUTTON_OK)
     return !table_->selection_model().empty();
 
   return true;
 }
 
 void WebShareTargetPickerView::OnSelectionChanged() {
   GetDialogClientView()->UpdateDialogButtons();
 }
 
 void WebShareTargetPickerView::OnDoubleClick() {
   GetDialogClientView()->AcceptWindow();
 }