Revert "Use Xvfb in isolated testing only if use_x11 is set"

chrome/interactive_ui_tests.isolate

Index: chrome/interactive_ui_tests.isolate
diff --git a/chrome/interactive_ui_tests.isolate b/chrome/interactive_ui_tests.isolate
index b008bb42e9e2828812cd3de38f17ae2ffaa7ea5e..bef0495321515a156f9aefdd3f2cf49177e05d16 100644
--- a/chrome/interactive_ui_tests.isolate
+++ b/chrome/interactive_ui_tests.isolate
@@ -3,18 +3,7 @@
 # found in the LICENSE file.
 {
   'conditions': [
-    ['use_x11==0', {
-      'variables': {
-        'command': [
-          '../testing/test_env.py',
-          '<(PRODUCT_DIR)/interactive_ui_tests<(EXECUTABLE_SUFFIX)',
-          '--test-launcher-bot-mode',
-          '--asan=<(asan)',
-          '--lsan=<(lsan)',
-        ],
-      },
-    }],
-    ['use_x11==1', {
+    ['OS=="linux"', {
       'variables': {
         'command': [
           '../testing/xvfb.py',
@@ -26,17 +15,17 @@
         ],
         'files': [
           '../testing/xvfb.py',
-          '<(PRODUCT_DIR)/xdisplaycheck<(EXECUTABLE_SUFFIX)',
+          '<(PRODUCT_DIR)/libffmpegsumo.so',
+          '<(PRODUCT_DIR)/libosmesa.so',
+          '<(PRODUCT_DIR)/libppapi_tests.so',
+          '<(PRODUCT_DIR)/pyproto/google/',
         ],
       },
     }],
-    ['OS=="linux"', {
+    ['OS=="linux" and use_ozone==0', {
       'variables': {
         'files': [
-          '<(PRODUCT_DIR)/libffmpegsumo.so',
-          '<(PRODUCT_DIR)/libosmesa.so',
-          '<(PRODUCT_DIR)/libppapi_tests.so',
-          '<(PRODUCT_DIR)/pyproto/google/',
+          '<(PRODUCT_DIR)/xdisplaycheck<(EXECUTABLE_SUFFIX)',
         ],
       },
     }],
@@ -79,6 +68,17 @@
         ],
       },
     }],
+    ['OS=="mac" or OS=="win"', {
+      'variables': {
+        'command': [
+          '../testing/test_env.py',
+          '<(PRODUCT_DIR)/interactive_ui_tests<(EXECUTABLE_SUFFIX)',
+          '--test-launcher-bot-mode',
+          '--asan=<(asan)',
+          '--lsan=<(lsan)',
+        ],
+      },
+    }],
     ['OS=="win"', {
       'variables': {
         'files': [