Reformat all gn files in /tools.

`gn format` recently changed its formatting behavior
for deps, source, and a few other elements when they
are assigned (with =) single-element lists to be consistent
with the formatting of updates (with +=) with single-element.

Now that we've rolled in a GN binary with the change,
reformat all files so that people don't get presubmit
warnings due to this.

This CL was uploaded by git cl split.

R=brucedawson@chromium.org

Bug: 1041419
Change-Id: I51294dc9b12ec3659dc430ee62c69b063c0c04df
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1997898
Auto-Submit: Nico Weber <thakis@chromium.org>
Reviewed-by: Bruce Dawson <brucedawson@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#731507}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 3fd99e95d33408d928561144562a5196a5a9fd37
diff --git a/BUILD.gn b/BUILD.gn
index 717c31a..1dc067c 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -3,9 +3,7 @@
 # found in the LICENSE file.
 
 executable("xdisplaycheck") {
-  sources = [
-    "xdisplaycheck.cc",
-  ]
+  sources = [ "xdisplaycheck.cc" ]
 
   configs += [ "//build/config/linux:x11" ]
 }