gn: Reduce stack memory use while parsing.

BUG=641454

Review-Url: https://codereview.chromium.org/2290713002
Cr-Original-Commit-Position: refs/heads/master@{#415181}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 9e92b9d9ef75b26947a46ed3bc2735fddc888b3f
2 files changed
tree: fc8f655245999df75e25e9db74549fb9efd9aefa
  1. tools/