Remove check for hardcoded Xwayland path in gdm.

diff --git a/daemon/gdm-local-display-factory.c b/daemon/gdm-local-display-factory.c
index 7de7b99c..065325f4 100644
--- a/daemon/gdm-local-display-factory.c
+++ b/daemon/gdm-local-display-factory.c
@@ -245,9 +245,9 @@ struct GdmDisplayServerConfiguration {
         const char *session_type;
 } display_server_configuration[] = {
 #ifdef ENABLE_WAYLAND_SUPPORT
-        { "wayland", GDM_KEY_WAYLAND_ENABLE, "/usr/bin/Xwayland", "wayland" },
+        { "wayland", GDM_KEY_WAYLAND_ENABLE, "", "wayland" },
 #endif
-        { "xorg", GDM_KEY_XORG_ENABLE, "/usr/bin/Xorg", "x11" },
+        { "xorg", GDM_KEY_XORG_ENABLE, "", "x11" },
         { NULL, NULL, NULL },
 };
 
@@ -269,9 +269,6 @@ display_server_enabled (GdmLocalDisplayFactory *factory,
                 if (!gdm_settings_direct_get_boolean (key, &enabled) || !enabled)
                         return FALSE;
 
-                if (!g_file_test (binary, G_FILE_TEST_IS_EXECUTABLE))
-                        return FALSE;
-
                 return TRUE;
         }
 
8b1c2f02fd905b1bf7c75632cef376'>refs</a><a class='active' href='/guix/log/tests/ui.scm'>log</a><a href='/guix/tree/tests/ui.scm?id=c4ff4928798b1c2f02fd905b1bf7c75632cef376'>tree</a><a href='/guix/commit/tests/ui.scm?id=c4ff4928798b1c2f02fd905b1bf7c75632cef376'>commit</a><a href='/guix/diff/tests/ui.scm?id=c4ff4928798b1c2f02fd905b1bf7c75632cef376'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/tests/ui.scm'>
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<div class='path'>path: <a href='/guix/log/?id=c4ff4928798b1c2f02fd905b1bf7c75632cef376'>root</a>/<a href='/guix/log/tests?id=c4ff4928798b1c2f02fd905b1bf7c75632cef376'>tests</a>/<a href='/guix/log/tests/ui.scm?id=c4ff4928798b1c2f02fd905b1bf7c75632cef376'>ui.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/ui.scm?id=c4ff4928798b1c2f02fd905b1bf7c75632cef376&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-03-25 16:02:53 +0100'>2020-03-25</span></td><td><a href='/guix/commit/tests/ui.scm?id=c136da3fbd92a5db1f889d37f0a7c938ccd63648'>tests: Adjust to 'show-manifest-transaction' changes.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-02-23 12:47:13 +0100'>2020-02-23</span></td><td><a href='/guix/commit/tests/ui.scm?id=fa99c4bbc7acdb8def9ce14a05aacb73f99fe3b1'>ui: (size-&gt;number "1.M") is correctly parsed.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-09-19 23:24:04 +0200'>2019-09-19</span></td><td><a href='/guix/commit/tests/ui.scm?id=d2cdef65605b9e14bfa02c3bf1612ab6b62f4a89'>ui: 'relevance' connects regexps with a logical and.</a><span class='msg-avail'>...</span></td><td>zimoun</td></tr>
cb4e6bd257'>tests: do not hard code HTTP ports</a><span class='msg-avail'>...</span></td><td>Maxime Devos</td></tr>