Fix compilation error in aura_init.cc

chrome/browser/ui/views/aura/aura_init.cc

Index: chrome/browser/ui/views/aura/aura_init.cc
diff --git a/chrome/browser/ui/views/aura/aura_init.cc b/chrome/browser/ui/views/aura/aura_init.cc
index 080848677a27071273552c37973ebab3c36661c0..33e633abe8dfab5d4ea022890975bceef0e45d27 100644
--- a/chrome/browser/ui/views/aura/aura_init.cc
+++ b/chrome/browser/ui/views/aura/aura_init.cc
@@ -35,6 +35,8 @@ class DemoWindowDelegate : public aura::WindowDelegate {
   virtual bool OnMouseEvent(aura::MouseEvent* event) OVERRIDE {
     return true;
   }
+  virtual void OnCaptureLost() OVERRIDE {
+  }
   virtual void OnPaint(gfx::Canvas* canvas) OVERRIDE {
     canvas->AsCanvasSkia()->drawColor(color_, SkXfermode::kSrc_Mode);
   }