Change the translation mechanism to use

`ActionView::Helpers::TranslationHelper`.

It has some advantages over only using `I18n.t`, such as the safe
translation if the key has the suffix `_html`.

lib/simple_form/components/hints.rb

@@ -9,7 +9,7 @@ module SimpleForm
           if hint.is_a?(String)
             html_escape(hint)
           else
-            content = translate(:hints)
+            content = translate_from_namespace(:hints)
             content.html_safe if content
           end
         end

lib/simple_form/components/labels.rb

@@ -66,7 +66,7 @@ module SimpleForm
 
       # First check labels translation and then human attribute name.
       def label_translation #:nodoc:
-        if SimpleForm.translate_labels && (translated_label = translate(:labels))
+        if SimpleForm.translate_labels && (translated_label = translate_from_namespace(:labels))
           translated_label
         elsif object.class.respond_to?(:human_attribute_name)
           object.class.human_attribute_name(reflection_or_attribute_name.to_s)

lib/simple_form/components/placeholders.rb

@@ -9,7 +9,7 @@ module SimpleForm
 
       def placeholder_text
         placeholder = options[:placeholder]
-        placeholder.is_a?(String) ? placeholder : translate(:placeholders)
+        placeholder.is_a?(String) ? placeholder : translate_from_namespace(:placeholders)
       end
     end
   end

lib/simple_form/inputs/base.rb

@@ -1,10 +1,13 @@
 require 'simple_form/i18n_cache'
 require 'active_support/core_ext/string/output_safety'
+require 'action_view'
+require 'action_view/helpers'
 
 module SimpleForm
   module Inputs
     class Base
       include ERB::Util
+      include ActionView::Helpers::TranslationHelper
 
       extend I18nCache
 
@@ -167,7 +170,7 @@ module SimpleForm
       #            email: 'E-mail.'
       #
       #  Take a look at our locale example file.
-      def translate(namespace, default = '')
+      def translate_from_namespace(namespace, default = '')
         model_names = lookup_model_names.dup
         lookups     = []
 
@@ -182,7 +185,7 @@ module SimpleForm
         lookups << :"defaults.#{reflection_or_attribute_name}"
         lookups << default
 
-        I18n.t(lookups.shift, scope: :"#{i18n_scope}.#{namespace}", default: lookups).presence
+        t(lookups.shift, scope: :"#{i18n_scope}.#{namespace}", default: lookups).presence
       end
 
       def merge_wrapper_options(options, wrapper_options)

lib/simple_form/inputs/collection_input.rb

@@ -98,7 +98,7 @@ module SimpleForm
       end
 
       def translate_collection
-        if translated_collection = translate(:options)
+        if translated_collection = translate_from_namespace(:options)
           @collection = collection.map do |key|
             [translated_collection[key] || key, key.to_s]
           end
@@ -110,7 +110,7 @@ module SimpleForm
         if options[key] == :translate
           namespace = key.to_s.pluralize
 
-          options[key] = translate(namespace, true)
+          options[key] = translate_from_namespace(namespace, true)
         end
       end
     end