Make schema definition column lookups agnostic w/r/t/ whether a key or symbol is passed. Fixes failing test in [2396].

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@2397 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb

@@ -160,7 +160,7 @@ module ActiveRecord
 
       # Returns a ColumnDefinition for the column with name +name+.
       def [](name)
-        @columns.find {|column| column.name == name}
+        @columns.find {|column| column.name.to_s == name.to_s}
       end
 
       # Instantiates a new column for the table.
@@ -216,4 +216,4 @@ module ActiveRecord
         end
     end
   end
-end
+end