Reformat remaining gn files.

`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.

Most changes have landed by now via `git cl split`.
This is what remains after two weeks.

Bug: 1041419
Change-Id: Ia813d744e57e5647266a91d4f6c725bf921fb11c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2024471
Commit-Queue: Nico Weber <thakis@chromium.org>
Auto-Submit: Nico Weber <thakis@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#735958}

diff --git a/third_party/decklink/BUILD.gn b/third_party/decklink/BUILD.gn
index 4de6471..4c0fa42 100644
--- a/third_party/decklink/BUILD.gn
+++ b/third_party/decklink/BUILD.gn

@@ -4,9 +4,7 @@
 
 if (is_mac) {
   static_library("decklink") {
-    sources = [
-      "mac/include/DeckLinkAPIDispatch.cpp",
-    ]
+    sources = [ "mac/include/DeckLinkAPIDispatch.cpp" ]
     libs = [
       "CoreFoundation.framework",
       "IOKit.framework",