Expose more details in FileReader::ReadFile signature

Return a status so callers can distinguish a missing file from an empty
file.  This allows our VirtualFileSystem test infrastructure to report
as missing any file for which it has no entry.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/test.h b/src/test.h
index 156e68a..488c243 100644
--- a/src/test.h
+++ b/src/test.h
@@ -145,7 +145,7 @@ struct VirtualFileSystem : public DiskInterface {
   virtual TimeStamp Stat(const string& path, string* err) const;
   virtual bool WriteFile(const string& path, const string& contents);
   virtual bool MakeDir(const string& path);
-  virtual string ReadFile(const string& path, string* err);
+  virtual Status ReadFile(const string& path, string* contents, string* err);
   virtual int RemoveFile(const string& path);
 
   /// An entry for a single in-memory file.