Don't double-strip static values

Author: nex3

doc-src/SASS_CHANGELOG.md

@@ -3,6 +3,10 @@
 * Table of contents
 {:toc}
 
+## 3.7.2 (Unreleased)
+
+* Fix another escaped-whitespace edge case.
+
 ## 3.7.1 (7 November 2018)
 
 * Properly handle escaped whitespace and other unusual characters.

lib/sass/scss/parser.rb

@@ -993,7 +993,7 @@ def value!
         if (val = tok(STATIC_VALUE))
           # If val ends with escaped whitespace, leave it be.
           val = val.lstrip.sub(/(?<!\\)\s*$/, '\1')
-          str = Sass::Script::Tree::Literal.new(Sass::Script::Value::String.new(val.strip))
+          str = Sass::Script::Tree::Literal.new(Sass::Script::Value::String.new(val))
           str.line = start_pos.line
           str.source_range = range(start_pos)
           return str