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Update mail to minimum version 2.5.4
Backport a super-simplified version of #6792, fixing
that #exists? and others can produce invalid SQL: "SELECT DISTINCT DISTINCT"

The combination of a :uniq => true association and the #distinct call
in #construct_limited_ids_condition combine to create invalid SQL, because
we're explicitly selecting DISTINCT, and also sending #distinct on to AREL,
via the relation#distinct_value.

Where #6792 was the forever fix, this is the minimal fix. Instead of
properly indicating the distinctness of the query through #uniq_value alone,
we use a literal select statement and set #uniq_value to always be falsey
Merge pull request #10616 from Empact/backport-distinct-distinct

Backport a super-simplified version of #6792, fixing that #exists? can produce invalid SQL: "SELECT DISTINCT DISTINCT"
Support include_root_in_json for ActiveResource properly.

This commit is a backport from
https://github.com/rails/activeresource/pull/29. The
ActiveResource's include_root_in_json option is broken for 3.2.x.
Merge pull request #10578 from dingle/lu/back_port_to_json_fix

Support include_root_in_json for ActiveResource properly.
destroys association records before saving/inserting new association records

This is a backport of #10417

fixes bug introduced by  #3329
These are the conditions necessary to reproduce the bug:
- For an association, autosave => true.
- An association record is being destroyed
- A new association record is being created.
- There is a unique index one of the association's fields.
- The record being created has the same value as the record being
destroyed on the indexed field.

Before, the deletion of records was postponed until after all
insertions/saves.  Therefore the new record with the identical value in
the indexed field caused a non-unique value error to be thrown at the
database
level.

With this fix, the deletions happen first, before the insertions/saves.
Therefore the record with the duplicate value is gone from the database
before the new record is created, thereby avoiding the non-uniuqe value
error.
Merge pull request #10646 from kennyj/fix_am_20130517

Fix ActionMailer testcase break with mail 2.5.4.
Conflicts:
	actionmailer/CHANGELOG.md
	actionmailer/test/mailers/base_mailer.rb
Merge pull request #10681 from jholton/3-2-stable-fix_association_auto_save

autosave_association issue that occurs when table has unique index (3.2.x backport)
Merge pull request #10713 from senny/10693_fix_primary_key_option_on_has_many

Fix the `:primary_key` option for `has_many` associations.
Conflicts:
	activerecord/CHANGELOG.md
	activerecord/lib/active_record/associations/has_many_association.rb