Mac: implement drag-and-drop of URLs to tabs/tab strip.

chrome/browser/cocoa/tab_strip_view.h

Index: chrome/browser/cocoa/tab_strip_view.h
diff --git a/chrome/browser/cocoa/tab_strip_view.h b/chrome/browser/cocoa/tab_strip_view.h
index c93ea8c551829fcc21cdcd46733a73ce42718816..29aa0eb0f70ba2cac118e53b9ae7cc58aa2118ec 100644
--- a/chrome/browser/cocoa/tab_strip_view.h
+++ b/chrome/browser/cocoa/tab_strip_view.h
@@ -7,12 +7,18 @@
 
 #import <Cocoa/Cocoa.h>
 
+#include "base/scoped_nsobject.h"
+#import "chrome/browser/cocoa/url_drop_target.h"
+
 // A view class that handles rendering the tab strip
 
 @interface TabStripView : NSView {
  @private
   NSTimeInterval lastMouseUp_;
 
+  // Handles being a drag-and-drop target.
+  scoped_nsobject<URLDropTargetHandler> dropHandler_;
+
   // Weak; the following come from the nib.
   NSButton* newTabButton_;
 }