Add app_list_presenterr pointer in app_list_presenter_delegate_mus to use dismiss function

chrome/browser/ui/ash/app_list/app_list_presenter_delegate_mus.h

Index: chrome/browser/ui/ash/app_list/app_list_presenter_delegate_mus.h
diff --git a/chrome/browser/ui/ash/app_list/app_list_presenter_delegate_mus.h b/chrome/browser/ui/ash/app_list/app_list_presenter_delegate_mus.h
index c7978db19222f0257f12e0378065b356821a3108..738daf03664b32ff8cf68cf8e5d4b934eec83086 100644
--- a/chrome/browser/ui/ash/app_list/app_list_presenter_delegate_mus.h
+++ b/chrome/browser/ui/ash/app_list/app_list_presenter_delegate_mus.h
@@ -5,12 +5,15 @@
 #ifndef CHROME_BROWSER_UI_ASH_APP_LIST_APP_LIST_PRESENTER_DELEGATE_MUS_H_
 #define CHROME_BROWSER_UI_ASH_APP_LIST_APP_LIST_PRESENTER_DELEGATE_MUS_H_
 
-#include "ui/app_list/presenter/app_list_presenter_delegate.h"
-
 #include "base/macros.h"
+#include "ui/app_list/presenter/app_list_presenter.h"

[mfomitchev, 2016/09/29 18:38:26]

You already forward declare this, why do you also need to #include? Generally
speaking, avoid includes in .h if you can forward declare instead - this reduces
linking time.

[thanhph, 2016/09/29 19:43:05]

I'm not sure where I forward declare this. Can you elaborate? If I remove the
include app_list_presenter.h, I get the error:

chrome/browser/ui/ash/app_list/app_list_presenter_delegate_mus.cc:111:17: error:
member access into incomplete type 'app_list::AppListPresenter'
      presenter_->Dismiss();
                ^

In app_list_service_ash.cc we include app_list_presenter_delegate.h but not
app_list_presenter.h 

[mfomitchev, 2016/09/29 20:00:36]

Put the include in the .cc. Forward declaration is what you have on line 16.
Take a look at this for more detail:
http://programmers.stackexchange.com/questions/195806/forward-declaration-vs-...

[thanhph, 2016/09/29 20:42:51]

I understand. Thanks!

+#include "ui/app_list/presenter/app_list_presenter_delegate.h"
+#include "ui/views/mus/pointer_watcher_event_router.h"

[mfomitchev, 2016/09/29 18:38:26]

Why do we need this?

[thanhph, 2016/09/29 19:43:04]

We need this for receiving mouse/touch callback events in the function
OnPointerEventObserved.

[mfomitchev, 2016/09/29 20:00:36]

Oh, ok, I see we are using PointerWatcherEventRouter in .cc. Same as above, move
the include to .cc.

[thanhph, 2016/09/29 20:42:51]

Ok. Done!

+#include "ui/views/pointer_watcher.h"
 
 namespace app_list {
 class AppListView;
+class AppListPresenter;
 class AppListViewDelegateFactory;
 }
 
@@ -18,10 +21,13 @@ class AppListViewDelegateFactory;
 // Responsible for laying out the app list UI as well as dismissing the app list
 // on in response to certain events (e.g. on mouse/touch gesture outside of the
 // app list bounds).
-class AppListPresenterDelegateMus : public app_list::AppListPresenterDelegate {
+class AppListPresenterDelegateMus : public app_list::AppListPresenterDelegate,
+                                    public views::PointerWatcher {
  public:
   explicit AppListPresenterDelegateMus(
+      app_list::AppListPresenter* presenter,
       app_list::AppListViewDelegateFactory* view_delegate_factory);
+
   ~AppListPresenterDelegateMus() override;
 
   // app_list::AppListPresenterDelegate:
@@ -32,9 +38,14 @@ class AppListPresenterDelegateMus : public app_list::AppListPresenterDelegate {
   void OnShown(int64_t display_id) override;
   void OnDismissed() override;
   void UpdateBounds() override;
+
   gfx::Vector2d GetVisibilityAnimationOffset(
       aura::Window* root_window) override;
 
+  void OnPointerEventObserved(const ui::PointerEvent& event,

[mfomitchev, 2016/09/29 18:38:26]

// views::PointerWatcher:
Also move to private.

[thanhph, 2016/09/29 19:43:04]

done. thanks!

[mfomitchev, 2016/09/29 20:00:36]

You forgot the comment.

[thanhph, 2016/09/29 20:42:51]

My bad. Comment is added!

+                              const gfx::Point& location_in_screen,
+                              views::Widget* target) override;
+
  private:
   // Whether the app list is visible (or in the process of being shown).
   bool is_visible_ = false;
@@ -45,6 +56,8 @@ class AppListPresenterDelegateMus : public app_list::AppListPresenterDelegate {
   // The current AppListView, owned by its widget.
   app_list::AppListView* view_ = nullptr;
 
+  app_list::AppListPresenter* presenter_;

[mfomitchev, 2016/09/29 18:38:26]

// Not owned. Pointer is guaranteed to be valid while this object is alive.

[thanhph, 2016/09/29 19:43:05]

done. thanks!

+
   DISALLOW_COPY_AND_ASSIGN(AppListPresenterDelegateMus);
 };