chromium: remove broken pulseSupport = false; override

As far as I can tell, this override broke almost 10 years ago in
8391241e0c.

When trying to build the fixup commit that followed immediately after
that (5f53fddf1e) the build fails with the
following error:

~~~
[11704/21910] CXX obj/media/media/vp9_compressed_header_parser.o
[11705/>
FAILED: obj/media/audio/audio/audio_manager_alsa.o
g++ -MMD -MF obj/media/audio/audio/audio_manager_alsa.o.d [...]
In file included from ../../media/audio/alsa/audio_manager_alsa.cc:28:0:
../../media/audio/pulse/audio_manager_pulse.h:8:30: fatal error: pulse/pulseaudio.h: No such file or directory
compilation terminated.
ninja: build stopped: subcommand failed.
~~~

And the same happens when trying to build chromium with
`pulseSupport = false;` and picking random releases between 17.03 and
now.

I don't think there is a good reason to keep this, especially since no
one bothered to test this in almost a decade. The chromium derivation is
a mess, so let's run with this rather small win and remove this broken,
mostly useless, obscure and untested permutation.

pkgs/applications/networking/browsers/chromium/common.nix

@@ -91,7 +91,6 @@
   cupsSupport ? true,
   cups ? null,
   proprietaryCodecs ? true,
-  pulseSupport ? false,
   libpulseaudio ? null,
   ungoogled ? false,
   ungoogled-chromium,
@@ -394,7 +393,9 @@ let
       libgcrypt
       cups
     ]
-    ++ lib.optional pulseSupport libpulseaudio;
+    ++ [
+      libpulseaudio
+    ];
 
     buildInputs = [
     ]
@@ -455,7 +456,9 @@ let
       libgcrypt
       cups
     ]
-    ++ lib.optional pulseSupport libpulseaudio;
+    ++ [
+      libpulseaudio
+    ];
 
     patches = [
       ./patches/cross-compile.patch
@@ -968,7 +971,7 @@ let
         use_vaapi = false;
         use_v4l2_codec = true;
       }
-      // lib.optionalAttrs pulseSupport {
+      // {
         use_pulseaudio = true;
         link_pulseaudio = true;
       }

pkgs/applications/networking/browsers/chromium/default.nix

@@ -32,7 +32,6 @@
   enableWideVine ? false,
   ungoogled ? false, # Whether to build chromium or ungoogled-chromium
   cupsSupport ? true,
-  pulseSupport ? config.pulseaudio or stdenv.hostPlatform.isLinux,
   commandLineArgs ? "",
   pkgsBuildBuild,
   pkgs,
@@ -76,7 +75,6 @@ let
       inherit
         proprietaryCodecs
         cupsSupport
-        pulseSupport
         ungoogled
         ;
       gnChromium = buildPackages.gn.override upstream-info.deps.gn;