Allow shared read access to parsed files (#310)

Author: luebbe

Source/DelphiAST.ProjectIndexer.pas

@@ -457,7 +457,7 @@ class function TProjectIndexer.SafeOpenFileStream(const fileName: string; var fi
 begin
   Result := true;
   try
-    readStream := TFileStream.Create(fileName, fmOpenRead);
+    readStream := TFileStream.Create(fileName, fmOpenRead or fmShareDenyWrite);
   except
     on E: EFCreateError do begin
       errorMsg := E.Message;