Change how ui::Clipboard is accessed so there's only one per thread.

content/shell/shell_aura.cc

Index: content/shell/shell_aura.cc
diff --git a/content/shell/shell_aura.cc b/content/shell/shell_aura.cc
index 9a0cf9f3d6bb67f16fefad7f67e19f1ebe74f1b3..3c6e6087cf65d9686bc5c9a881d06a8bffc0e049 100644
--- a/content/shell/shell_aura.cc
+++ b/content/shell/shell_aura.cc
@@ -52,13 +52,6 @@ class ShellViewsDelegateAura : public ViewsDelegate {
   }
 
   // Overridden from ViewsDelegate:
-  virtual ui::Clipboard* GetClipboard() const OVERRIDE {
-    if (!clipboard_.get()) {
-      clipboard_.reset(new ui::Clipboard);
-    }
-    return clipboard_.get();
-  }
-
   virtual void SaveWindowPlacement(const Widget* window,
                                    const std::string& window_name,
                                    const gfx::Rect& bounds,
@@ -111,7 +104,6 @@ class ShellViewsDelegateAura : public ViewsDelegate {
   }
 
  private:
-  mutable scoped_ptr<ui::Clipboard> clipboard_;
   bool use_transparent_windows_;
 
   DISALLOW_COPY_AND_ASSIGN(ShellViewsDelegateAura);