Use Xvfb in isolated testing only if use_x11 is set

base/base_unittests.isolate

Index: base/base_unittests.isolate
diff --git a/base/base_unittests.isolate b/base/base_unittests.isolate
index f561d209cf5920b95b36562e9edc01f0db678469..26f4c2b38915a3fae15ff8b145a152ea9337f274 100644
--- a/base/base_unittests.isolate
+++ b/base/base_unittests.isolate
@@ -10,25 +10,31 @@
         ],
       },
     }],
-    ['OS=="linux"', {
+    ['use_x11==0', {
       'variables': {
         'command': [
-          '../testing/xvfb.py',
-          '<(PRODUCT_DIR)',
+          '../testing/test_env.py',
           '<(PRODUCT_DIR)/base_unittests<(EXECUTABLE_SUFFIX)',
           '--brave-new-test-launcher',
           '--test-launcher-bot-mode',
           '--asan=<(asan)',
           '--lsan=<(lsan)',
         ],
-        'files': [
-          '../testing/xvfb.py',
-        ],
       },
     }],
-    ['OS=="linux" and use_ozone==0', {
+    ['use_x11==1', {
       'variables': {
+        'command': [
+          '../testing/xvfb.py',
+          '<(PRODUCT_DIR)',
+          '<(PRODUCT_DIR)/base_unittests<(EXECUTABLE_SUFFIX)',
+          '--brave-new-test-launcher',
+          '--test-launcher-bot-mode',
+          '--asan=<(asan)',
+          '--lsan=<(lsan)',
+        ],
         'files': [
+          '../testing/xvfb.py',
           '<(PRODUCT_DIR)/xdisplaycheck<(EXECUTABLE_SUFFIX)',
         ],
       },
@@ -42,18 +48,6 @@
         'read_only': 1,
       },
     }],
-    ['OS=="mac" or OS=="win"', {
-      'variables': {
-        'command': [
-          '../testing/test_env.py',
-          '<(PRODUCT_DIR)/base_unittests<(EXECUTABLE_SUFFIX)',
-          '--brave-new-test-launcher',
-          '--test-launcher-bot-mode',
-          '--asan=<(asan)',
-          '--lsan=<(lsan)',
-        ],
-      },
-    }],
     ['OS=="win" and (fastbuild==0 or fastbuild==1)', {
       'variables': {
         'files': [