arc: Set custom icon in shelf for ARC apps.

chrome/browser/ui/ash/launcher/app_window_launcher_item_controller.cc

Index: chrome/browser/ui/ash/launcher/app_window_launcher_item_controller.cc
diff --git a/chrome/browser/ui/ash/launcher/app_window_launcher_item_controller.cc b/chrome/browser/ui/ash/launcher/app_window_launcher_item_controller.cc
index 11032d2c9b43aa5320f6e96f104a30d2836894fb..05a335ea59d6280ed3bd0758e5bd7543096f8e8d 100644
--- a/chrome/browser/ui/ash/launcher/app_window_launcher_item_controller.cc
+++ b/chrome/browser/ui/ash/launcher/app_window_launcher_item_controller.cc
@@ -27,6 +27,8 @@ void AppWindowLauncherItemController::AddWindow(ui::BaseWindow* app_window) {
   aura::Window* window = app_window->GetNativeWindow();
   if (window)
     observed_windows_.Add(window);
+  if (GetLastActiveWindow() == app_window)

[xiyuan, 2017/05/18 16:22:48]

As mentioned in the other comment, it might be better to fold this into
OnActiveWindowChanged impl.

[khmel, 2017/05/18 17:29:34]

Done.

+    OnActiveWindowChanged(app_window);
 }
 
 AppWindowLauncherItemController::WindowList::iterator
@@ -49,8 +51,8 @@ void AppWindowLauncherItemController::RemoveWindow(ui::BaseWindow* app_window) {
     NOTREACHED();
     return;
   }
-  OnWindowRemoved(app_window);
   windows_.erase(iter);
+  OnActiveWindowChanged(GetLastActiveWindow());
 }
 
 ui::BaseWindow* AppWindowLauncherItemController::GetAppWindow(
@@ -65,6 +67,7 @@ void AppWindowLauncherItemController::SetActiveWindow(aura::Window* window) {
   ui::BaseWindow* app_window = GetAppWindow(window);
   if (app_window)
     last_active_window_ = app_window;
+  OnActiveWindowChanged(GetLastActiveWindow());
 }
 
 AppWindowLauncherItemController*
@@ -119,6 +122,12 @@ void AppWindowLauncherItemController::ActivateIndexedApp(size_t index) {
   ShowAndActivateOrMinimize(*it);
 }
 
+ui::BaseWindow* AppWindowLauncherItemController::GetLastActiveWindow() {
+  if (last_active_window_)
+    return last_active_window_;
+  return windows_.empty() ? nullptr : windows_.front();
+}
+
 void AppWindowLauncherItemController::OnWindowPropertyChanged(
     aura::Window* window,
     const void* key,