GN: Use std::unique_ptr for owned pointers in ImportManager.

BUG=602726

Review URL: https://codereview.chromium.org/1886453002

Cr-Original-Commit-Position: refs/heads/master@{#387997}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 647a1af223628bb4e15b69a29ca257477282b737
2 files changed
tree: f87c7285f99998f36808c18cfb00a54c8a3c6b0c
  1. tools/