Also accept long values in lists of scalar values.

dashboard/dashboard/add_point.py

Index: dashboard/dashboard/add_point.py
diff --git a/dashboard/dashboard/add_point.py b/dashboard/dashboard/add_point.py
index 7e1d620e9f98d21c3062b68e04f6a9807fe20789..e88a607db2dc6fa8da36c537ab5c4ac32e8df97b 100644
--- a/dashboard/dashboard/add_point.py
+++ b/dashboard/dashboard/add_point.py
@@ -425,7 +425,7 @@ def _ExtractValueAndError(trace):
       if trace.get('none_value_reason'):
         return float('nan'), float('nan')
       raise BadRequestError('Expected list of scalar values, got: %r' % values)
-    if not all(isinstance(v, float) or isinstance(v, int) for v in values):
+    if not all(_IsNumber(v) for v in values):
       raise BadRequestError('Non-number found in values list: %r' % values)
     value = math_utils.Mean(values)
     std = trace.get('std')
@@ -441,6 +441,10 @@ def _ExtractValueAndError(trace):
   raise BadRequestError('Invalid value type in chart object: %r' % trace_type)
 
 
+def _IsNumber(v):
+  return isinstance(v, float) or isinstance(v, int) or isinstance(v, long)
+
+
 def _EscapeName(name):
   """Escapes a trace name so it can be stored in a row.