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 05533c9dab20257fa64290bf2f0e62b48e277476..22a3ec9d81049de54eeb5302ad9a1e3c20920042 100644
--- a/chrome/browser/ui/panels/panel.h
+++ b/chrome/browser/ui/panels/panel.h
@@ -63,6 +63,16 @@ class Panel : public BrowserWindow,
 
   bool IsDrawingAttention() const;
 
+  // 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;