Support dragging panels to stack and snap.

chrome/browser/ui/panels/panel.h

Index: chrome/browser/ui/panels/panel.h
diff --git a/chrome/browser/ui/panels/panel.h b/chrome/browser/ui/panels/panel.h
index 70c9c39c3a5eda87a5ef4c904b9021b8579937b4..3251b60b0d850304a06564ed3284f7727b6e8171 100644
--- a/chrome/browser/ui/panels/panel.h
+++ b/chrome/browser/ui/panels/panel.h
@@ -27,6 +27,7 @@ class PanelCollection;
 class PanelHost;
 class PanelManager;
 class Profile;
+class StackedPanelCollection;
 
 namespace content {
 class WebContents;
@@ -88,6 +89,8 @@ class Panel : public BaseWindow,
   CommandUpdater* command_updater();
   Profile* profile() const;
 
+  const extensions::Extension* GetExtension() const;
+
   // Returns web contents of the panel, if any. There may be none if web
   // contents have not been added to the panel yet.
   content::WebContents* GetWebContents() const;
@@ -176,6 +179,8 @@ class Panel : public BaseWindow,
     collection_ = new_collection;
   }
 
+  StackedPanelCollection* stack() const;

[dcheng, 2013/01/10 22:39:03]

Do we want to be returning a non-const pointer here? If so, maybe the method
shouldn't be marked const (although there's some inconsistencies here already,
such as on line 89 and 90, it seems better to not mark pointers to mutable class
state as being returned by const functions).

[jianli, 2013/01/10 23:23:23]

Yes we need non-const pointer since we need to call non-const method. I do not
want to remove const method modifier since this is simply a getter and it should
not mean to have something that can update any data in Panel.

+
   ExpansionState expansion_state() const { return expansion_state_; }
   const gfx::Size& min_size() const { return min_size_; }
   const gfx::Size& max_size() const { return max_size_; }
@@ -295,6 +300,9 @@ class Panel : public BaseWindow,
   // Updates UI to reflect that the web cotents receives the focus.
   void WebContentsFocused(content::WebContents* contents);
 
+  // Moves the panel by delta instantly.
+  void MoveByInstantly(const gfx::Vector2d& delta_origin);
+
  protected:
   // Panel can only be created using PanelManager::CreatePanel() or subclass.
   // |app_name| is the default title for Panels when the page content does not
@@ -325,8 +333,6 @@ class Panel : public BaseWindow,
   // Configures the renderer for auto resize (if auto resize is enabled).
   void ConfigureAutoResize(content::WebContents* web_contents);
 
-  const extensions::Extension* GetExtension() const;
-
   // Load the app's image, firing a load state change when loaded.
   void UpdateAppIcon();