(maint) Removes Ruby 1.8-specific method

Ruby 1.8 hit its end-of-life almost nine years ago. This commit
removes logic to call a different version of the normalize_string
method when running on Ruby 1.8.

Author: mhashizume

lib/facter/custom_facts/util/normalization.rb

@@ -38,11 +38,7 @@ def normalize(value)
       #
       # Attempt to normalize and validate the given string.
       #
-      # On Ruby 1.8 the string is checked by stripping out all non UTF-8
-      # characters and comparing the converted string to the original. If they
-      # do not match then the string is considered invalid.
-      #
-      # On Ruby 1.9+, the string is validate by checking that the string encoding
+      # The string is validated by checking that the string encoding
       # is UTF-8 and that the string content matches the encoding. If the string
       # is not an expected encoding then it is converted to UTF-8.
       #
@@ -51,27 +47,16 @@ def normalize(value)
       # @param value [String]
       # @return [void]
 
-      if RUBY_VERSION.match?(/^1\.8/)
-        require 'iconv'
-
-        def normalize_string(value)
-          converted = Iconv.conv('UTF-8//IGNORE', 'UTF-8', value)
-          raise NormalizationError, "String #{value.inspect} is not valid UTF-8" if converted != value
+      def normalize_string(value)
+        value = value.encode(Encoding::UTF_8)
 
-          value
+        unless value.valid_encoding?
+          raise NormalizationError, "String #{value.inspect} doesn't match the reported encoding #{value.encoding}"
         end
-      else
-        def normalize_string(value)
-          value = value.encode(Encoding::UTF_8)
 
-          unless value.valid_encoding?
-            raise NormalizationError, "String #{value.inspect} doesn't match the reported encoding #{value.encoding}"
-          end
-
-          value
-        rescue EncodingError
-          raise NormalizationError, "String encoding #{value.encoding} is not UTF-8 and could not be converted to UTF-8"
-        end
+        value
+      rescue EncodingError
+        raise NormalizationError, "String encoding #{value.encoding} is not UTF-8 and could not be converted to UTF-8"
       end
 
       # Validate all elements of the array.