Converted the remaining GPU bots to recipes.

masters/master.chromium.webkit/master.cfg

Index: masters/master.chromium.webkit/master.cfg
diff --git a/masters/master.chromium.webkit/master.cfg b/masters/master.chromium.webkit/master.cfg
index 052228cd01e7f02423d4cb571bf628a3745219a0..43dc8d77d84f5b4a536e455c933906c73e1b36ef 100644
--- a/masters/master.chromium.webkit/master.cfg
+++ b/masters/master.chromium.webkit/master.cfg
@@ -33,9 +33,7 @@ import master_chromiumos_latest_cfg
 import master_mac_latest_cfg
 import master_linux_latest_cfg
 import master_android_latest_cfg
-import master_win_gpu_latest_cfg
-import master_mac_gpu_latest_cfg
-import master_linux_gpu_latest_cfg
+import master_gpu_latest_cfg
 
 master_source_cfg.Update(config, ActiveMaster, c)
 master_win_webkit_pinned_cfg.Update(config, ActiveMaster, c)
@@ -50,9 +48,7 @@ master_mac_latest_cfg.Update(config, ActiveMaster, c)
 master_linux_latest_cfg.Update(config, ActiveMaster, c)
 master_chromiumos_latest_cfg.Update(config, ActiveMaster, c)
 master_android_latest_cfg.Update(config, ActiveMaster, c)
-master_win_gpu_latest_cfg.Update(config, ActiveMaster, c)
-master_mac_gpu_latest_cfg.Update(config, ActiveMaster, c)
-master_linux_gpu_latest_cfg.Update(config, ActiveMaster, c)
+master_gpu_latest_cfg.Update(config, ActiveMaster, c)
 
 # This will be enabled when the master is split.
 if TREE_GATE_KEEPER: