Remove unecessary copying of priv/include for Rebar 3 deps

Author: josevalim

lib/mix/lib/mix/tasks/deps.compile.ex

@@ -206,20 +206,6 @@ defmodule Mix.Tasks.Deps.Compile do
 
     File.mkdir_p!(dep_path)
     File.write!(config_path, rebar_config(dep))
-
-    # We need to copy/symlink include/priv in case it is
-    # needed for compiling the dependency itself. Later on
-    # we will build the whole structure and also symlink/copy
-    # ebin.
-    #
-    # Note both configurations are necessary when using the
-    # bare compiler with compiler output dir, otherwise includes
-    # and priv files can't be found. For example, without those
-    # options, we were unable to compile certifi, which uses
-    # both parse transforms and reads from priv at compilation.
-    Mix.Utils.symlink_or_copy(Path.join(opts[:dest], "include"), Path.join(dep_path, "include"))
-    Mix.Utils.symlink_or_copy(Path.join(opts[:dest], "priv"), Path.join(dep_path, "priv"))
-
     do_command(dep, config, cmd, false, env)
   end