Re-introduce ImportDeclaration to the parser

src/globals.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_GLOBALS_H_
 #define V8_GLOBALS_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 699 matching lines @@
     (static_cast<uint64_t>(kHoleNanUpper32) << 32) | kHoleNanLower32;
 
 
 // The order of this enum has to be kept in sync with the predicates below.
 enum VariableMode {
   // User declared variables:
   VAR,             // declared via 'var', and 'function' declarations
 
   CONST_LEGACY,    // declared via legacy 'const' declarations
 
-  LET,             // declared via 'let' declarations
+  LET,             // declared via 'let' declarations (first lexical)
 
   CONST,           // declared via 'const' declarations
 
+  IMPORT,          // declared via 'import' declarations (last lexical)
+
   // Variables introduced by the compiler:
   INTERNAL,        // like VAR, but not user-visible (may or may not
                    // be in a context)
 
   TEMPORARY,       // temporary variables (not user-visible), stack-allocated
                    // unless the scope as a whole has forced context allocation
 
   DYNAMIC,         // always require dynamic lookup (we don't know
                    // the declaration)
 
   DYNAMIC_GLOBAL,  // requires dynamic lookup, but we know that the
                    // variable is global unless it has been shadowed
                    // by an eval-introduced variable
 
   DYNAMIC_LOCAL    // requires dynamic lookup, but we know that the
                    // variable is local and where it is unless it
                    // has been shadowed by an eval-introduced
                    // variable
 };
 
 
 inline bool IsDynamicVariableMode(VariableMode mode) {
   return mode >= DYNAMIC && mode <= DYNAMIC_LOCAL;
 }
 
 
 inline bool IsDeclaredVariableMode(VariableMode mode) {
-  return mode >= VAR && mode <= CONST;
+  return mode >= VAR && mode <= IMPORT;
 }
 
 
 inline bool IsLexicalVariableMode(VariableMode mode) {
-  return mode == LET || mode == CONST;
+  return mode >= LET && mode <= IMPORT;
 }
 
 
 inline bool IsImmutableVariableMode(VariableMode mode) {
-  return mode == CONST || mode == CONST_LEGACY;
+  return mode == CONST || mode == CONST_LEGACY || mode == IMPORT;
 }
 
 
 // ES6 Draft Rev3 10.2 specifies declarative environment records with mutable
 // and immutable bindings that can be in two states: initialized and
 // uninitialized. In ES5 only immutable bindings have these two states. When
 // accessing a binding, it needs to be checked for initialization. However in
 // the following cases the binding is initialized immediately after creation
 // so the initialization check can always be skipped:
 // 1. Var declared local variables.
@@ skipping 124 matching lines @@
   DCHECK(IsValidFunctionKind(kind));
   return kind &
          (FunctionKind::kBaseConstructor | FunctionKind::kSubclassConstructor |
           FunctionKind::kDefaultConstructor);
 }
 } }  // namespace v8::internal
 
 namespace i = v8::internal;
 
 #endif  // V8_GLOBALS_H_