Revert "Performance: freeze cached rows instead of duping"

This reverts commit cd8e653.

Author: jeremy

activerecord/lib/active_record/base.rb

@@ -612,7 +612,7 @@ def all(*args)
       #   Post.find_by_sql ["SELECT title FROM posts WHERE author = ? AND created > ?", author_id, start_date]
       #   > [#<Post:0x36bff9c @attributes={"first_name"=>"The Cheap Man Buys Twice"}>, ...]
       def find_by_sql(sql)
-        connection.select_all(sanitize_sql(sql), "#{name} Load").map { |record| instantiate(record) }
+        connection.select_all(sanitize_sql(sql), "#{name} Load").collect! { |record| instantiate(record) }
       end
 
       # Checks whether a record exists in the database that matches conditions given.  These conditions

activerecord/lib/active_record/connection_adapters/abstract/query_cache.rb

@@ -72,12 +72,21 @@ def columns_with_query_cache(*args)
 
       private
         def cache_sql(sql)
-          if @query_cache.has_key?(sql)
-            log_info(sql, "CACHE", 0.0)
-            @query_cache[sql]
+          result =
+            if @query_cache.has_key?(sql)
+              log_info(sql, "CACHE", 0.0)
+              @query_cache[sql]
+            else
+              @query_cache[sql] = yield
+            end
+
+          if Array === result
+            result.collect { |row| row.dup }
           else
-            @query_cache[sql] = yield.freeze
+            result.duplicable? ? result.dup : result
           end
+        rescue TypeError
+          result
         end
     end
   end