rename private method to avoid overriding

postgres, quote table names when fetching the primary key (#5920)

to the block.

Thanks @tenderlove

use Rails backtrace in tests

This will make easier to permit date/time attributes generated by
helpers like date_select.

[Sven Schwyn + Rafael Mendonça França]

Fix middleware cache tests enabling rack_cache

fix Example: Rename tools/profile_requires -> tools/profile

This reverts commit abf8de85.
We should take a deeper look to those cases flat_map doesn't do deep
flattening.

irb(main):002:0> [[[1,3], [1,2]]].map{|i| i}.flatten
=> [1, 3, 1, 2]
irb(main):003:0> [[[1,3], [1,2]]].flat_map{|i| i}
=> [[1, 3], [1, 2]]

Disable Rack::Cache by default

bare is true.

We need to change this since coffee-rails loads ActionView that loads
core_ext/array/access.

This was added in Rails 4 and we don't need changelog entries to
behavior changes

[ci skip]

ActionController::Parameters#permit! is recursive

Sine page caching was remove from the core we don't have the
page_cache_directory anymore

Extract AP Page and Action caching from Rails

Updated comments for [ci skip]

- Changed the comments documentation for the update_column(s) methods to add a little bit of clarity

Move the CacheHelper#fragment_name_with_digest to be public

Count returns 0 without querying if parent is not saved

Patches `CollectionAssociation#count` to return 0 without querying
if the parent record is new. Consider the following code:

    class Account
      has_many :dossiers
    end

    class Dossier
      belongs_to :account
    end

    a = Account.new
    a.dossiers.build

    # before patch
    a.dossiers.count
    # SELECT COUNT(*) FROM "dossiers" WHERE "dossiers"."account_id" IS NULL
    # => 0

    # after
    a.dosiers.count # fires without sql query
    # => 0

Fixes #1856.