Avoid (@_var ||= nil) pattern by using initialize methods and ensuring everyone calls super as expected.

This cleans up the last bits of deprecation stuff from form_for helper.
However there is still a bug when using :as => foo[], with index. The
classes and ids are being generated using [], such as foo[]_edit. This
bug already existed but it was not detected before.

Signed-off-by: NMikel Lindsaar <raasdnil@gmail.com>

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

This makes the use of passwords secure by default if you want to render
the value of the password_field you have to do for instance
f.password_field(:password, :value => @user.password) # =>
<input type=password id=user_password name=user[password]
value=#{@user.password} />

Make InstanceTagMethods#value_before_type_cast raise if the model don't respond to attr_before_type_cast or attr method

[#3374] [#5471 state:committed]

  Before: f.label :title, nil, :class => 'title'
  After : f.label :title, :class => 'title'

[#5267 state:committed]
Signed-off-by: NSantiago Pastorino <santiago@wyeworks.com>

[#3374 state:committed]

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

make text_field and hidden_field omit the value attribute if the developer explicitly passes in :value => nil [#4839 state:resolved]
Signed-off-by: NMichael Koziarski <michael@koziarski.com>

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

[#4902 state:committed]
Signed-off-by: NJeremy Kemper <jeremy@bitsweat.net>

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

Signed-off-by: NJosé Valim <jose.valim@gmail.com>