Use ui_unittests instead of gfx_unittests.

masters/master.chromium.linux/master_linux_cfg.py

Index: masters/master.chromium.linux/master_linux_cfg.py
===================================================================
--- masters/master.chromium.linux/master_linux_cfg.py	(revision 143294)
+++ masters/master.chromium.linux/master_linux_cfg.py	(working copy)
@@ -45,8 +45,8 @@
   'ipc_tests',             # from test target unit
   'sync_unit_tests',       # from test target unit
   'content_unittests',     # from test target unit
+  'ui_unittests',          # from test target unit
   'unit_tests',            # from test target unit
-  'gfx_unittests',         # from test target unit
   'browser_tests',
 ]
 
@@ -150,7 +150,6 @@
   'compositor_unittests',
   'content_unittests',
   'crypto_unittests',
-  'gfx_unittests',
   'googleurl_unittests',
   'gpu_unittests',
   'interactive_ui_tests',
@@ -162,6 +161,7 @@
   'remoting_unittests',
   'safe_browsing_tests',
   'sql_unittests',
+  'ui_unittests',
 ]
 
 # B('Linux (aura)', 'f_linux_rel_aura', 'compile', 'linux_rel',