Reformat GN files.

`gn format` recently [1] 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.

CL generated with:
$ git ls-files | grep BUILD.gn | xargs gn format
$ gn format build_overrides/build.gni
$ gn format build_overrides/gtest.gni
$ gn format modules/audio_coding/audio_coding.gni
$ gn format webrtc.gni
$ gn format .gn

Plus a few manual changes to add exceptions for
"public_deps" (after changing these lines the presubmit
started to complain).

[1] - https://gn-review.googlesource.com/c/gn/+/6860

Bug: webrtc:11302
Change-Id: Iac29d23c1618ebef925c972e2891cd9f4e8cd613
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/166882
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30334}
diff --git a/api/task_queue/BUILD.gn b/api/task_queue/BUILD.gn
index 00be784..4c9f591 100644
--- a/api/task_queue/BUILD.gn
+++ b/api/task_queue/BUILD.gn
@@ -15,9 +15,7 @@
     "task_queue_base.h",
     "task_queue_factory.h",
   ]
-  sources = [
-    "task_queue_base.cc",
-  ]
+  sources = [ "task_queue_base.cc" ]
 
   deps = [
     "../../rtc_base:checks",
@@ -75,12 +73,8 @@
   if (!is_ios && !is_android) {
     poisonous = [ "default_task_queue" ]
   }
-  sources = [
-    "default_task_queue_factory.h",
-  ]
-  deps = [
-    ":task_queue",
-  ]
+  sources = [ "default_task_queue_factory.h" ]
+  deps = [ ":task_queue" ]
 
   if (rtc_enable_libevent) {
     sources += [ "default_task_queue_factory_libevent.cc" ]
@@ -100,9 +94,7 @@
 if (rtc_include_tests) {
   rtc_library("task_queue_default_factory_unittests") {
     testonly = true
-    sources = [
-      "default_task_queue_factory_unittest.cc",
-    ]
+    sources = [ "default_task_queue_factory_unittest.cc" ]
     deps = [
       ":default_task_queue_factory",
       ":task_queue_test",