Fix the crash that could occur when the window is closed while web contents drag is in progress.

content/public/browser/web_contents_view.h

Index: content/public/browser/web_contents_view.h
diff --git a/content/public/browser/web_contents_view.h b/content/public/browser/web_contents_view.h
index 019e40164e95b909039f065d75ee3c2f50633b67..5009a220d2afb09873efc8723b071bfcf4ec0b61 100644
--- a/content/public/browser/web_contents_view.h
+++ b/content/public/browser/web_contents_view.h
@@ -98,12 +98,6 @@ class CONTENT_EXPORT WebContentsView {
   // invoked, SetInitialFocus is invoked.
   virtual void RestoreFocus() = 0;
 
-  // If we try to close the tab while a drag is in progress, we crash.  These
-  // methods allow the WebContents to determine if a drag is in progress and
-  // postpone the tab closing.
-  virtual bool IsDoingDrag() const = 0;
-  virtual void CancelDragAndCloseTab() = 0;
-
   // Returns the current drop data, if any.
   virtual WebDropData* GetDropData() const = 0;