Revert "Fix an internal bug in QB where() escaping"

This reverts commit 43afc71b777b00cfc2638add6fa3c47d333c5e04.
diff --git a/system/database/DB_query_builder.php b/system/database/DB_query_builder.php
index da88204..6ea7841 100644
--- a/system/database/DB_query_builder.php
+++ b/system/database/DB_query_builder.php
@@ -657,7 +657,10 @@
 
 			if ($v !== NULL)
 			{
-				$v = ' '.$this->escape($v);
+				if ($escape === TRUE)
+				{
+					$v = ' '.$this->escape($v);
+				}
 
 				if ( ! $this->_has_operator($k))
 				{