Extract `NumericData` model for tests

Currently `NumericData` model is defined some places.

activerecord/test/cases/base_test.rb

@@ -15,6 +15,7 @@
 require "models/column_name"
 require "models/subscriber"
 require "models/comment"
+require "models/numeric_data"
 require "models/minimalistic"
 require "models/warehouse_thing"
 require "models/parrot"
@@ -908,13 +909,6 @@ def test_default
     end
   end
 
-  class NumericData < ActiveRecord::Base
-    self.table_name = "numeric_data"
-
-    attribute :my_house_population, :integer
-    attribute :atoms_in_universe, :integer
-  end
-
   def test_big_decimal_conditions
     m = NumericData.new(
       bank_balance: 1586.43,

activerecord/test/cases/calculations_test.rb

@@ -8,6 +8,7 @@
 require "models/possession"
 require "models/topic"
 require "models/reply"
+require "models/numeric_data"
 require "models/minivan"
 require "models/speedometer"
 require "models/ship_part"
@@ -17,14 +18,6 @@
 require "models/rating"
 require "models/post"
 
-class NumericData < ActiveRecord::Base
-  self.table_name = "numeric_data"
-
-  attribute :world_population, :integer
-  attribute :my_house_population, :integer
-  attribute :atoms_in_universe, :integer
-end
-
 class CalculationsTest < ActiveRecord::TestCase
   fixtures :companies, :accounts, :topics, :speedometers, :minivans, :books
 

activerecord/test/cases/dirty_test.rb

@@ -4,10 +4,7 @@
 require "models/parrot"
 require "models/person"   # For optimistic locking
 require "models/aircraft"
-
-class NumericData < ActiveRecord::Base
-  self.table_name = "numeric_data"
-end
+require "models/numeric_data"
 
 class DirtyTest < ActiveRecord::TestCase
   include InTimeZone

activerecord/test/models/numeric_data.rb

+class NumericData < ActiveRecord::Base
+  self.table_name = "numeric_data"
+end