Remove support for building frog at the top-level: it requires node.

dart/dart.gyp

Index: dart/dart.gyp
===================================================================
--- dart/dart.gyp	(revision 1142)
+++ dart/dart.gyp	(working copy)
@@ -22,20 +22,21 @@
         'runtime/dart-runtime.gyp:process_test',
       ],
     },
-    {
-      'target_name': 'frog',
-      'type': 'none',
-      'dependencies': [
-        'frog/dart-frog.gyp:frog',
-      ],
-    },
-    {
-      'target_name': 'frogsh',
-      'type': 'none',
-      'dependencies': [
-        'frog/dart-frog.gyp:frogsh',
-      ],
-    },
+    # TODO(ngeoffray): Requires node to be in the path.
+    #{
+    #  'target_name': 'frog',
+    #  'type': 'none',
+    #  'dependencies': [
+    #    'frog/dart-frog.gyp:frog',
+    #  ],
+    #},
+    #{
+    #  'target_name': 'frogsh',
+    #  'type': 'none',
+    #  'dependencies': [
+    #    'frog/dart-frog.gyp:frogsh',
+    #  ],
+    #},
     # TODO(ngeoffray): Fling does not have proper dependencies,
     # so don't build it for now.
     #{