Add links to the "Using GN build" presentation.

Change-Id: I9a65229a501dc867b07aa49e56e033a571818078
Reviewed-on: https://gn-review.googlesource.com/c/3460
Reviewed-by: Brett Wilson <brettw@chromium.org>
Commit-Queue: Dirk Pranke <dpranke@google.com>

README.md

diff --git a/README.md b/README.md
index b64b26b..a370e00 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,8 @@
 
 GN is a meta-build system that generates build files for
 [Ninja](https://ninja-build.org). There is documentation in
-[docs/](https://gn.googlesource.com/gn/+/master/docs/).
+[docs/](https://gn.googlesource.com/gn/+/master/docs/) and
+[a presentation on it](https://docs.google.com/presentation/d/15Zwb53JcncHfEwHpnG_PoIbbzQ3GQi_cpujYwbpcbZo/edit?usp=sharing).
 
 ## Getting started
 

docs/faq.md

diff --git a/docs/faq.md b/docs/faq.md
index 55d8aef..699df3d 100644
--- a/docs/faq.md
+++ b/docs/faq.md
@@ -50,3 +50,9 @@
 Yes! If you create a group target called "default" in the top-level (root)
 build file, i.e., "//:default", GN will tell Ninja to build that by
 default, rather than building everything.
+
+## Are there any public presentations on GN?
+
+[There's at least one](https://docs.google.com/presentation/d/15Zwb53JcncHfEwHpnG_PoIbbzQ3GQi_cpujYwbpcbZo/edit?usp=sharing), from 2015. There
+haven't been big changes since then apart from moving it to a standalone
+repo, so it should still be relevant.