Make PreParser track valid left hand sides.

src/preparser.cc

Index: src/preparser.cc
diff --git a/src/preparser.cc b/src/preparser.cc
index 398f32744cb61ff6c5e5af317d22b8d117f37b9f..e9f29b3dba275394401158a01654e4e68667549e 100644
--- a/src/preparser.cc
+++ b/src/preparser.cc
@@ -874,7 +874,7 @@ PreParser::Expression PreParser::ParseLeftHandSideExpression(bool* ok) {
         if (result.IsThis()) {
           result = Expression::ThisProperty();
         } else {
-          result = Expression::Default();
+          result = Expression::Property();
         }
         break;
       }
@@ -891,7 +891,7 @@ PreParser::Expression PreParser::ParseLeftHandSideExpression(bool* ok) {
         if (result.IsThis()) {
           result = Expression::ThisProperty();
         } else {
-          result = Expression::Default();
+          result = Expression::Property();
         }
         break;
       }
@@ -980,7 +980,7 @@ PreParser::Expression PreParser::ParseMemberExpressionContinuation(
         if (expression.IsThis()) {
           expression = Expression::ThisProperty();
         } else {
-          expression = Expression::Default();
+          expression = Expression::Property();
         }
         break;
       }
@@ -990,7 +990,7 @@ PreParser::Expression PreParser::ParseMemberExpressionContinuation(
         if (expression.IsThis()) {
           expression = Expression::ThisProperty();
         } else {
-          expression = Expression::Default();
+          expression = Expression::Property();
         }
         break;
       }
@@ -1102,7 +1102,6 @@ PreParser::Expression PreParser::ParseFunctionLiteral(
 
     int end_position = scanner()->location().end_pos;
     CheckOctalLiteral(start_position, end_position, CHECK_OK);
-    return Expression::StrictFunction();
   }
 
   return Expression::Default();