Add Value FromDict to Telemetry

tools/telemetry/telemetry/value/list_of_scalar_values.py

Index: tools/telemetry/telemetry/value/list_of_scalar_values.py
diff --git a/tools/telemetry/telemetry/value/list_of_scalar_values.py b/tools/telemetry/telemetry/value/list_of_scalar_values.py
index 5bd95d41633d22eea97cb5513b43c8b6ec7ca58c..821158fdb459e3c44bda469a36751e049bb97a9b 100644
--- a/tools/telemetry/telemetry/value/list_of_scalar_values.py
+++ b/tools/telemetry/telemetry/value/list_of_scalar_values.py
@@ -59,8 +59,8 @@ class ListOfScalarValues(value_module.Value):
     return (super(ListOfScalarValues, self).IsMergableWith(that) and
             self.same_page_merge_policy == that.same_page_merge_policy)
 
-  @classmethod
-  def GetJSONTypeName(cls):
+  @staticmethod
+  def GetJSONTypeName():
     return 'list_of_scalar_values'
 
   def AsDict(self):
@@ -68,6 +68,13 @@ class ListOfScalarValues(value_module.Value):
     d['values'] = self.values
     return d
 
+  @staticmethod
+  def FromDict(value_dict, page_dict):
+    kwargs = value_module.Value.GetConstructorKwArgs(value_dict, page_dict)
+    kwargs['values'] = value_dict['values']
+
+    return ListOfScalarValues(**kwargs)
+
   @classmethod
   def MergeLikeValuesFromSamePage(cls, values):
     assert len(values) > 0