commit 1ae777a027b5243924f2b3ba774067a7bf5926cf
author andybons <andybons@chromium.org> Thu Sep 17 22:24:32 2015
committer Commit bot <commit-bot@chromium.org> Thu Sep 17 22:25:11 2015
tree 355dd07e13ce0fcfd0192fe2309f2a86c755aee0
parent e0d6c38940042d5cdc5b9ebe52504480493569fd

[GN]: Precompiled header support for GCC.

+ Adds `gcc` as an option for `precompiled_header_type`
+ Fixes a bug where build targets had superfluous pch deps.
+ GCH files are compiled using the `-x <header lang>` and used via the `-header` flag. Since the two are mutually exclusive and we didn’t want to add `-header` to every build target line, the global cflags_* vars contain `-include` and each pch build target includes its own copy of the cflags_* values while replacing `-include` with `-x <header lang>`

BUG=297681

Review URL: https://codereview.chromium.org/1292983004

Cr-Commit-Position: refs/heads/master@{#349518}