[es6] support template literals after MemberExpression

src/preparser.h

Index: src/preparser.h
diff --git a/src/preparser.h b/src/preparser.h
index a17296349b362df6afefbb5b8538d7c030915270..8e0bacb463b591d8e0bac68f10163f54d072fbce 100644
--- a/src/preparser.h
+++ b/src/preparser.h
@@ -589,6 +589,8 @@ class ParserBase : public Traits {
   ExpressionT ParseArrowFunctionLiteral(int start_pos, ExpressionT params_ast,
                                         bool* ok);
   ExpressionT ParseTemplateLiteral(ExpressionT tag, int start, bool* ok);
+  ExpressionT ParseTemplateLiteralAsMemberExpressionContinuation(
+      ExpressionT tag, bool* ok);
   void AddTemplateExpression(ExpressionT);
   ExpressionT ParseSuperExpression(bool is_new, bool* ok);
 
@@ -2655,18 +2657,8 @@ ParserBase<Traits>::ParseLeftHandSideExpression(bool* ok) {
 
       case Token::TEMPLATE_SPAN:
       case Token::TEMPLATE_TAIL: {
-        int pos;
-        if (scanner()->current_token() == Token::IDENTIFIER) {
-          pos = position();
-        } else {
-          pos = peek_position();
-          if (result->IsFunctionLiteral() && mode() == PARSE_EAGERLY) {
-            // If the tag function looks like an IIFE, set_parenthesized() to
-            // force eager compilation.
-            result->AsFunctionLiteral()->set_parenthesized();
-          }
-        }
-        result = ParseTemplateLiteral(result, pos, CHECK_OK);
+        result = ParseTemplateLiteralAsMemberExpressionContinuation(
+            result, CHECK_OK);
         break;
       }
 
@@ -2842,6 +2834,12 @@ ParserBase<Traits>::ParseMemberExpressionContinuation(ExpressionT expression,
         }
         break;
       }
+      case Token::TEMPLATE_SPAN:
+      case Token::TEMPLATE_TAIL: {
+        expression = ParseTemplateLiteralAsMemberExpressionContinuation(
+            expression, CHECK_OK);
+        break;
+      }
       default:
         return expression;
     }
@@ -2853,6 +2851,25 @@ ParserBase<Traits>::ParseMemberExpressionContinuation(ExpressionT expression,
 
 template <class Traits>
 typename ParserBase<Traits>::ExpressionT
+ParserBase<Traits>::ParseTemplateLiteralAsMemberExpressionContinuation(
+    ExpressionT expression, bool* ok) {
+  int pos;
+  if (scanner()->current_token() == Token::IDENTIFIER) {
+    pos = position();
+  } else {
+    pos = peek_position();
+    if (expression->IsFunctionLiteral() && mode() == PARSE_EAGERLY) {
+      // If the tag function looks like an IIFE, set_parenthesized() to
+      // force eager compilation.
+      expression->AsFunctionLiteral()->set_parenthesized();
+    }
+  }
+  return ParseTemplateLiteral(expression, pos, CHECK_OK);
+}
+
+
+template <class Traits>
+typename ParserBase<Traits>::ExpressionT
 ParserBase<Traits>::ParseArrowFunctionLiteral(int start_pos,
                                               ExpressionT params_ast,
                                               bool* ok) {