Draggable peeking/fullscreen launcher with transparent background.

ui/app_list/views/all_apps_tile_item_view.cc

 // Copyright 2014 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 "ui/app_list/views/all_apps_tile_item_view.h"
 
 #include "base/metrics/histogram_macros.h"
 #include "ui/app_list/app_list_constants.h"
+#include "ui/app_list/app_list_features.h"
+#include "ui/app_list/views/app_list_view.h"
 #include "ui/app_list/views/contents_view.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/image/canvas_image_source.h"
 #include "ui/resources/grit/ui_resources.h"
 #include "ui/strings/grit/ui_strings.h"
+#include "ui/views/widget/widget.h"
 
 namespace app_list {
 
 namespace {
 
 class AllAppsImageSource : public gfx::CanvasImageSource {
  public:
   AllAppsImageSource(const gfx::ImageSkia& icon, const gfx::Size& size)
       : gfx::CanvasImageSource(size, false), icon_(icon) {}
   ~AllAppsImageSource() override {}
@@ skipping 31 matching lines @@
 
   SetIcon(image);
 }
 
 void AllAppsTileItemView::ButtonPressed(views::Button* sender,
                                         const ui::Event& event) {
   UMA_HISTOGRAM_ENUMERATION(kPageOpenedHistogram, AppListModel::STATE_APPS,
                             AppListModel::STATE_LAST);
 
   contents_view_->SetActiveState(AppListModel::STATE_APPS);
+  if(features::IsFullscreenAppListEnabled()){

[vadimt, 2017/05/22 23:36:57]

Space before {? Git cl format?

[newcomer, 2017/05/25 23:10:51]

Done.

+   AppListView *app_list_view =
+       (AppListView*)GetAncestorWithClassName("AppListView");

[vadimt, 2017/05/22 23:36:57]

Please try properly plumbing AppListView as opposed to use non-type-safe
approaches.

[newcomer, 2017/05/25 23:10:51]

Done.

+   app_list_view->ToFullscreen();
+  }
 }
 
 }  // namespace app_list