[WPE] Unconditionally enable the Mesa software rasterizer when runnin…

…g tests

https://bugs.webkit.org/show_bug.cgi?id=274148

Reviewed by Carlos Garcia Campos.

We can't expect all the WPE post-commit test bots to have a GPU, so in order to improve test
reproducability independently from the test host graphics setup, enable the Mesa software
rasterizer.

* Tools/Scripts/webkitpy/port/wpe.py:
(WPEPort.setup_environ_for_server):

Canonical link: https://commits.webkit.org/278862@main

Tools/Scripts/webkitpy/port/wpe.py

@@ -62,8 +62,7 @@ def _driver_class(self):
     def setup_environ_for_server(self, server_name=None):
         environment = super(WPEPort, self).setup_environ_for_server(server_name)
         environment['WEBKIT_NICOSIA_PAINTING_THREADS'] = '0'
-        if self.get_option('wpe_platform_api'):
-            environment['LIBGL_ALWAYS_SOFTWARE'] = '1'
+        environment['LIBGL_ALWAYS_SOFTWARE'] = '1'
         self._copy_value_from_environ_if_set(environment, 'XR_RUNTIME_JSON')
         self._copy_value_from_environ_if_set(environment, 'BREAKPAD_MINIDUMP_DIR')
         return environment