Revert "Fixed Issue #2884 ActiveModel::SecurePassword code / rdoc conflict; an elucidated explanation has been provided and ActiveModel en-locale updated to present a less confusing attribute name for 'password_digest' in form errors due to "has_secure_password""

This reverts commit ddbea9474e.

Reason: Includes non-doc changes.

activemodel/lib/active_model/locale/en.yml

@@ -1,8 +1,4 @@
 en:
-  attributes:
-    # Prevent confusion in form errors due to 'has_secure_password'
-    password_digest: "Password"
-
   errors:
     # The default format to use in full error messages.
     format: "%{attribute} %{message}"

activemodel/lib/active_model/secure_password.rb

@@ -10,19 +10,6 @@ module ActiveModel
       # a "password_confirmation" attribute) are automatically added.
       # You can add more validations by hand if need be.
       #
-      # Note: the implementation of <tt>has_secure_password</tt> enforces presence validation
-      # on the <tt>:password_digest</tt> attribute rather than on <tt>:password</tt>, which is
-      # in fact a virtual reader attribute.  However, <tt>validates_confirmation_of</tt> ensures
-      # an indirect means of presence validation of <tt>:password</tt> if the
-      # <tt>:password_confirmation</tt> attribute is not nil.
-      #
-      # You may want to add presence validation on <tt>:password</tt> for the benefit of your forms
-      #
-      #   class User < ActiveRecord::Base
-      #     has_secure_password
-      #     validates :password, :presence => { :on => :create }
-      #   end
-      #
       # You need to add bcrypt-ruby (~> 3.0.0) to Gemfile to use has_secure_password:
       #
       #   gem 'bcrypt-ruby', '~> 3.0.0'