Don't lstrip ESCAPEd text

fixes regression caused 92c33a222f

lib/haml/parser.rb

@@ -244,7 +244,9 @@ module Haml
         return push flat_script(line.strip!(2), false) if line.text[1] == FLAT_SCRIPT
         return push plain(line.strip!(1), false) if line.text[1] == ?\s
         push plain(line)
-      when ESCAPE; push plain(line.strip!(1))
+      when ESCAPE
+        line.text = line.text[1..-1]
+        push plain(line)
       else; push plain(line)
       end
     end

test/results/just_stuff.xhtml

@@ -24,6 +24,7 @@ stuff followed by whitespace
   - character
   %p foo
   yee\ha
+     don't lstrip me
 </p>
 <!-- Short comment -->
 <!--

test/templates/just_stuff.haml

@@ -29,6 +29,7 @@
   \- character
   \%p foo
   \yee\ha
+  \   don't lstrip me
 / Short comment
 /
   This is a block comment