Remove deprecated #acronym_regex method from Inflections

Author: rafaelfranca

actionpack/test/dispatch/request_test.rb

@@ -763,7 +763,6 @@ class RequestMethod < BaseRequestTest
 
   test "post uneffected by local inflections" do
     existing_acronyms = ActiveSupport::Inflector.inflections.acronyms.dup
-    assert_deprecated { ActiveSupport::Inflector.inflections.acronym_regex.dup }
     begin
       ActiveSupport::Inflector.inflections do |inflect|
         inflect.acronym "POS"

activesupport/CHANGELOG.md

@@ -1,3 +1,7 @@
+*   Remove deprecated `#acronym_regex` method from `Inflections`.
+
+    *Rafael Mendonça França*
+
 *   Fix `String#safe_constantize` throwing a `LoadError` for incorrectly cased constant references.
 
     *Keenan Brock*

activesupport/lib/active_support/inflector/inflections.rb

@@ -65,8 +65,7 @@ def self.instance(locale = :en)
         @__instance__[locale] ||= new
       end
 
-      attr_reader :plurals, :singulars, :uncountables, :humans, :acronyms, :acronym_regex
-      deprecate :acronym_regex
+      attr_reader :plurals, :singulars, :uncountables, :humans, :acronyms
 
       attr_reader :acronyms_camelize_regex, :acronyms_underscore_regex # :nodoc:
 

activesupport/test/inflector_test.rb

@@ -224,12 +224,6 @@ def test_underscore_acronym_sequence
     assert_equal("json_html_api", ActiveSupport::Inflector.underscore("JSONHTMLAPI"))
   end
 
-  def test_acronym_regexp_is_deprecated
-    assert_deprecated do
-      ActiveSupport::Inflector.inflections.acronym_regex
-    end
-  end
-
   def test_underscore
     CamelToUnderscore.each do |camel, underscore|
       assert_equal(underscore, ActiveSupport::Inflector.underscore(camel))