Use Ash's ShelfWindowWatcher for app panel windows.

ash/common/shelf/shelf_window_watcher.cc

Index: ash/common/shelf/shelf_window_watcher.cc
diff --git a/ash/common/shelf/shelf_window_watcher.cc b/ash/common/shelf/shelf_window_watcher.cc
index 22a6e7f7fd86e2605c68e3955c04eec728704a3f..757b5aff52eeed3f42b7ba5c23dda9cf105d241f 100644
--- a/ash/common/shelf/shelf_window_watcher.cc
+++ b/ash/common/shelf/shelf_window_watcher.cc
@@ -19,6 +19,7 @@
 #include "ui/display/display.h"
 #include "ui/display/screen.h"
 #include "ui/gfx/image/image_skia.h"
+#include "ui/resources/grit/ui_resources.h"
 
 namespace ash {
 namespace {
@@ -27,8 +28,17 @@ namespace {
 void UpdateShelfItemForWindow(ShelfItem* item, WmWindow* window) {
   item->type = static_cast<ShelfItemType>(
       window->GetIntProperty(WmWindowProperty::SHELF_ITEM_TYPE));
-  const int icon =
-      window->GetIntProperty(WmWindowProperty::SHELF_ICON_RESOURCE_ID);
+
+  // Prefer app icons over window icons, they're typically larger.
+  gfx::ImageSkia image = window->GetAppIcon();
+  if (image.isNull())
+    image = window->GetWindowIcon();
+  if (!image.isNull()) {
+    item->image = image;
+    return;
+  }
+
+  int icon = window->GetIntProperty(WmWindowProperty::SHELF_ICON_RESOURCE_ID);
   if (icon != kInvalidImageResourceID)
     item->image = *ResourceBundle::GetSharedInstance().GetImageSkiaNamed(icon);
 }
@@ -52,8 +62,10 @@ void ShelfWindowWatcher::ContainerWindowObserver::OnWindowTreeChanged(
     WmWindow* window,
     const TreeChangeParams& params) {
   if (!params.old_parent && params.new_parent &&
-      params.new_parent->GetShellWindowId() ==
-          kShellWindowId_DefaultContainer) {
+      (params.new_parent->GetShellWindowId() ==
+           kShellWindowId_DefaultContainer ||
+       params.new_parent->GetShellWindowId() ==
+           kShellWindowId_PanelContainer)) {
     // A new window was created in the default container.

[James Cook, 2016/11/02 17:53:43]

nit: update comment

[msw, 2016/11/10 21:07:46]

Done.

     window_watcher_->OnUserWindowAdded(params.target);
   }
@@ -75,8 +87,10 @@ ShelfWindowWatcher::UserWindowObserver::~UserWindowObserver() {}
 void ShelfWindowWatcher::UserWindowObserver::OnWindowPropertyChanged(
     WmWindow* window,
     WmWindowProperty property) {
-  if (property == WmWindowProperty::SHELF_ITEM_TYPE ||
-      property == WmWindowProperty::SHELF_ICON_RESOURCE_ID) {
+  if (property == WmWindowProperty::APP_ICON ||
+      property == WmWindowProperty::SHELF_ITEM_TYPE ||
+      property == WmWindowProperty::SHELF_ICON_RESOURCE_ID ||
+      property == WmWindowProperty::WINDOW_ICON) {
     window_watcher_->OnUserWindowPropertyChanged(window);
   }
 }
@@ -98,6 +112,8 @@ ShelfWindowWatcher::ShelfWindowWatcher(ShelfModel* model)
   for (WmWindow* root : WmShell::Get()->GetAllRootWindows()) {
     observed_container_windows_.Add(
         root->GetChildByShellWindowId(kShellWindowId_DefaultContainer));
+    observed_container_windows_.Add(
+        root->GetChildByShellWindowId(kShellWindowId_PanelContainer));
   }
 
   display::Screen::GetScreen()->AddObserver(this);
@@ -109,18 +125,20 @@ ShelfWindowWatcher::~ShelfWindowWatcher() {
 }
 
 void ShelfWindowWatcher::AddShelfItem(WmWindow* window) {
+  managed_user_windows_.insert(window);
   ShelfItem item;
   ShelfID id = model_->next_id();
   item.status = window->IsActive() ? STATUS_ACTIVE : STATUS_RUNNING;
   UpdateShelfItemForWindow(&item, window);
   window->SetIntProperty(WmWindowProperty::SHELF_ID, id);
   std::unique_ptr<ShelfItemDelegate> item_delegate(
-      new ShelfWindowWatcherItemDelegate(window));
+      new ShelfWindowWatcherItemDelegate(id, window));
   model_->SetShelfItemDelegate(id, std::move(item_delegate));
   model_->Add(item);
 }
 
 void ShelfWindowWatcher::RemoveShelfItem(WmWindow* window) {
+  managed_user_windows_.erase(window);
   int shelf_id = window->GetIntProperty(WmWindowProperty::SHELF_ID);
   DCHECK_NE(shelf_id, kInvalidShelfID);
   int index = model_->ItemIndexByID(shelf_id);
@@ -175,9 +193,11 @@ void ShelfWindowWatcher::OnUserWindowDestroying(WmWindow* window) {
 void ShelfWindowWatcher::OnUserWindowPropertyChanged(WmWindow* window) {
   if (window->GetIntProperty(WmWindowProperty::SHELF_ITEM_TYPE) ==
       TYPE_UNDEFINED) {
-    // Removes ShelfItem for |window| when it has a ShelfItem.
-    if (window->GetIntProperty(WmWindowProperty::SHELF_ID) != kInvalidShelfID)
+    // Remove |window|'s ShelfItem if it was added by this ShelfWindowWatcher.
+    if (window->GetIntProperty(WmWindowProperty::SHELF_ID) != kInvalidShelfID &&
+        managed_user_windows_.count(window) > 0) {
       RemoveShelfItem(window);
+    }
     return;
   }
 
@@ -208,10 +228,14 @@ void ShelfWindowWatcher::OnDisplayAdded(const display::Display& new_display) {
 
   // When the primary root window's display get removed, the existing root
   // window is taken over by the new display and the observer is already set.
-  WmWindow* container =
+  WmWindow* default_container =
       root->GetChildByShellWindowId(kShellWindowId_DefaultContainer);
-  if (!observed_container_windows_.IsObserving(container))
-    observed_container_windows_.Add(container);
+  if (!observed_container_windows_.IsObserving(default_container))
+    observed_container_windows_.Add(default_container);
+  WmWindow* panel_container =
+      root->GetChildByShellWindowId(kShellWindowId_PanelContainer);
+  if (!observed_container_windows_.IsObserving(panel_container))
+    observed_container_windows_.Add(panel_container);
 }
 
 void ShelfWindowWatcher::OnDisplayRemoved(const display::Display& old_display) {