Fix error handling in libsass compiler for Python 3

Author: Andrey Fedoseev

static_precompiler/compilers/libsass.py

@@ -50,7 +50,7 @@ def compile_file(self, source_path):
             else:
                 compiled = sass.compile(filename=full_source_path, include_paths=self.load_paths)
         except sass.CompileError as e:
-            raise exceptions.StaticCompilationError(e.message)
+            raise exceptions.StaticCompilationError(encoding.force_str(e))
 
         compiled = encoding.force_str(compiled)
         sourcemap = encoding.force_str(sourcemap)
@@ -72,7 +72,7 @@ def compile_source(self, source):
         try:
             compiled = sass.compile(string=source, indented=self.indented)
         except sass.CompileError as e:
-            raise exceptions.StaticCompilationError(e.message)
+            raise exceptions.StaticCompilationError(encoding.force_str(e))
 
         compiled = encoding.force_str(compiled)