Reformat all gn files in /components/constrained_window.

`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=msw@chromium.org

Bug: 1041419
Change-Id: Iba2927b856fc1c7f0cf7ab44ce8a3b62516745d4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1997750
Auto-Submit: Nico Weber <thakis@chromium.org>
Reviewed-by: Michael Wasserman <msw@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#730908}

components/constrained_window/BUILD.gn

@@ -39,9 +39,7 @@ static_library("constrained_window") {
 
 source_set("unit_tests") {
   testonly = true
-  sources = [
-    "constrained_window_views_unittest.cc",
-  ]
+  sources = [ "constrained_window_views_unittest.cc" ]
 
   deps = [
     ":constrained_window",