Modified cancel and interrupt processing to avoid race with history.

chrome/browser/download/download_request_handle.h

Index: chrome/browser/download/download_request_handle.h
diff --git a/chrome/browser/download/download_request_handle.h b/chrome/browser/download/download_request_handle.h
index 0f26697221ca0fcf9c66d6908af5863abee3d1d3..00a40c70e87b1687a9e58058a7c0a47097beda44 100644
--- a/chrome/browser/download/download_request_handle.h
+++ b/chrome/browser/download/download_request_handle.h
@@ -37,11 +37,15 @@ class DownloadRequestHandle {
   TabContents* GetTabContents() const;
   DownloadManager* GetDownloadManager() const;
 
-  // Pause or resume the matching URL request.
+  // Pause or resume the matching URL request.  Note that while these
+  // do not modify the DownloadRequestHandle, they do modify the
+  // request the handle refers to.
   void PauseRequest() const;
   void ResumeRequest() const;
 
-  // Cancel the request
+  // Cancel the request.  Note that while this does not
+  // modify the DownloadRequestHandle, it does modify the
+  // request the handle refers to.
   void CancelRequest() const;
 
   std::string DebugString() const;