Files.app: Add an private API to get a download URL

chrome/browser/chromeos/drive/fake_file_system.h

Index: chrome/browser/chromeos/drive/fake_file_system.h
diff --git a/chrome/browser/chromeos/drive/fake_file_system.h b/chrome/browser/chromeos/drive/fake_file_system.h
index 5625ccaab8c5cf4086386078fa7b561613c6efb0..ecc60b91f3d92f609d9edf89affc68f6b03bc764 100644
--- a/chrome/browser/chromeos/drive/fake_file_system.h
+++ b/chrome/browser/chromeos/drive/fake_file_system.h
@@ -107,10 +107,11 @@ class FakeFileSystem : public FileSystemInterface {
                               const SearchMetadataCallback& callback) OVERRIDE;
   virtual void GetAvailableSpace(
       const GetAvailableSpaceCallback& callback) OVERRIDE;
-  virtual void GetShareUrl(
-      const base::FilePath& file_path,
-      const GURL& embed_origin,
-      const GetShareUrlCallback& callback) OVERRIDE;
+  virtual void GetShareUrl(const base::FilePath& file_path,
+                           const GURL& embed_origin,
+                           const GetUrlCallback& callback) OVERRIDE;
+  virtual void GetDownloadUrl(const base::FilePath& file_path,
+                              const GetUrlCallback& callback) OVERRIDE;
   virtual void GetMetadata(
       const GetFilesystemMetadataCallback& callback) OVERRIDE;
   virtual void MarkCacheFileAsMounted(