Remove //net from GN exec_script whitelist.

This used to use gypi_to_gn to read sources. Since that has been removed, this whitelist entry is no longer needed.

Clarify the comment about gypi_to_gn usage: it's no longer the main reason for a whitelist entry.

Review-Url: https://codereview.chromium.org/2701573002
Cr-Commit-Position: refs/heads/master@{#450842}
1 file changed