Add PanelOverflowStrip to handle panel overflow.

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 094e523da7e86fdfc93b50a92cfbe2029a63859c..c9f4eab76d2a2a153a3d0b44b196089547375016 100644
--- a/chrome/browser/ui/panels/panel.h
+++ b/chrome/browser/ui/panels/panel.h
@@ -69,6 +69,18 @@ class Panel : public BrowserWindow,
   // b) it remains on top when an app exits full screen mode.
   void FullScreenModeChanged(bool is_full_screen);
 
+  void MoveOutOfOverflow();
+
+  // Ensures that the panel is fully visible, that is, not obscured by other
+  // top-most windows.
+  void EnsureFullyVisible();
+
+  int TitleOnlyHeight() const;
+
+  // Returns the size of the panel when it is iconified, as shown on the
+  // overflow area.
+  gfx::Size IconOnlySize() const;
+
   // BrowserWindow overrides.
   virtual void Show() OVERRIDE;
   virtual void ShowInactive() OVERRIDE;