Remove all mac 10.5 bots from the main waterfall. Create placeholders for 10.7 bots.

masters/master.chromium/slaves.cfg

Index: masters/master.chromium/slaves.cfg
===================================================================
--- masters/master.chromium/slaves.cfg	(revision 143624)
+++ masters/master.chromium/slaves.cfg	(working copy)
@@ -362,32 +362,32 @@
     'version': '10.6',
     'bits': '64',
   },
+#  {
+#    'master': 'Chromium',
+#    'hostname': 'vm612-m1',
+#    'builder': 'Mac10.7 Tests (1)',
+#    'os': 'mac',
+#    'version': '10.7',
+#    'bits': '64',
+#  },
+#  {
+#    'master': 'Chromium',
+#    'hostname': 'vm613-m1',
+#    'builder': 'Mac10.7 Tests (2)',
+#    'os': 'mac',
+#    'version': '10.7',
+#    'bits': '64',
+#  },
+#  {
+#    'master': 'Chromium',
+#    'hostname': 'vm614-m1',
+#    'builder': 'Mac10.7 Tests (3)',
+#    'os': 'mac',
+#    'version': '10.7',
+#    'bits': '64',
+#  },
   {
     'master': 'Chromium',
-    'hostname': 'vm612-m1',
-    'builder': 'Mac10.5 Tests (1)',
-    'os': 'mac',
-    'version': '10.5',
-    'bits': '64',
-  },
-  {
-    'master': 'Chromium',
-    'hostname': 'vm613-m1',
-    'builder': 'Mac10.5 Tests (2)',
-    'os': 'mac',
-    'version': '10.5',
-    'bits': '64',
-  },
-  {
-    'master': 'Chromium',
-    'hostname': 'vm614-m1',
-    'builder': 'Mac10.5 Tests (3)',
-    'os': 'mac',
-    'version': '10.5',
-    'bits': '64',
-  },
-  {
-    'master': 'Chromium',
     'hostname': 'vm603-m1',
     'builder': 'Mac10.6 Tests (1)',
     'os': 'mac',
@@ -418,40 +418,40 @@
     'version': '10.6',
     'bits': '64',
   },
+#  {
+#    'master': 'Chromium',
+#    'hostname': 'vm615-m1',
+#    'builder': 'Mac 10.7 Tests (dbg)(1)',
+#    'os': 'mac',
+#    'version': '10.7',
+#    'bits': '64',
+#  },
+#  {
+#    'master': 'Chromium',
+#    'hostname': 'vm616-m1',
+#    'builder': 'Mac 10.7 Tests (dbg)(2)',
+#    'os': 'mac',
+#    'version': '10.7',
+#    'bits': '64',
+#  },
+#  {
+#    'master': 'Chromium',
+#    'hostname': 'vm617-m1',
+#    'builder': 'Mac 10.7 Tests (dbg)(3)',
+#    'os': 'mac',
+#    'version': '10.7',
+#    'bits': '64',
+#  },
+#  {
+#    'master': 'Chromium',
+#    'hostname': 'vm618-m1',
+#    'builder': 'Mac 10.7 Tests (dbg)(4)',
+#    'os': 'mac',
+#    'version': '10.7',
+#    'bits': '64',
+#  },
   {
     'master': 'Chromium',
-    'hostname': 'vm615-m1',
-    'builder': 'Mac 10.5 Tests (dbg)(1)',
-    'os': 'mac',
-    'version': '10.5',
-    'bits': '64',
-  },
-  {
-    'master': 'Chromium',
-    'hostname': 'vm616-m1',
-    'builder': 'Mac 10.5 Tests (dbg)(2)',
-    'os': 'mac',
-    'version': '10.5',
-    'bits': '64',
-  },
-  {
-    'master': 'Chromium',
-    'hostname': 'vm617-m1',
-    'builder': 'Mac 10.5 Tests (dbg)(3)',
-    'os': 'mac',
-    'version': '10.5',
-    'bits': '64',
-  },
-  {
-    'master': 'Chromium',
-    'hostname': 'vm618-m1',
-    'builder': 'Mac 10.5 Tests (dbg)(4)',
-    'os': 'mac',
-    'version': '10.5',
-    'bits': '64',
-  },
-  {
-    'master': 'Chromium',
     'hostname': 'vm606-m1',
     'builder': 'Mac 10.6 Tests (dbg)(1)',
     'os': 'mac',