permissionrequest API for guest Download.

chrome/browser/prerender/prerender_contents.cc

Index: chrome/browser/prerender/prerender_contents.cc
diff --git a/chrome/browser/prerender/prerender_contents.cc b/chrome/browser/prerender/prerender_contents.cc
index e82ad17a6e92e2ba9fc67526c6d4d55eec3d68db..ff326460e5c36966d796a22562c0ad33db43d107 100644
--- a/chrome/browser/prerender/prerender_contents.cc
+++ b/chrome/browser/prerender/prerender_contents.cc
@@ -78,12 +78,14 @@ class PrerenderContents::WebContentsDelegateImpl
     return NULL;
   }
 
-  virtual bool CanDownload(RenderViewHost* render_view_host,
-                           int request_id,
-                           const std::string& request_method) OVERRIDE {
+  virtual void CanDownload(
+      RenderViewHost* render_view_host,
+      int request_id,
+      const std::string& request_method,
+      const base::Callback<void(bool)>& callback) OVERRIDE {
     prerender_contents_->Destroy(FINAL_STATUS_DOWNLOAD);
     // Cancel the download.
-    return false;
+    callback.Run(false);
   }
 
   virtual bool ShouldCreateWebContents(