[ESNext] Ship import() and import.meta

import() is shipping by default in Chrome 63 and import.meta is
shipping in Chrome 64 already.

The flag still exists so that embedders can turn off the feature
if required.

Bug: v8:5785, v8:6693
Change-Id: Ie6c8f90927958022900f677ea5a771527111aece
Reviewed-on: https://chromium-review.googlesource.com/889658
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50913}

src/flag-definitions.h

@@ -204,7 +204,6 @@ DEFINE_IMPLICATION(harmony_class_fields, harmony_private_fields)
 // Features that are still work in progress (behind individual flags).
 #define HARMONY_INPROGRESS(V)                                            \
   V(harmony_string_trimming, "harmony String.prototype.trim{Start,End}") \
-  V(harmony_import_meta, "harmony import.meta property")                 \
   V(harmony_array_prototype_values, "harmony Array.prototype.values")    \
   V(harmony_function_sent, "harmony function.sent")                      \
   V(harmony_do_expressions, "harmony do-expressions")                    \
@@ -218,17 +217,18 @@ DEFINE_IMPLICATION(harmony_class_fields, harmony_private_fields)
   V(harmony_restrict_constructor_return,                                \
     "harmony disallow non undefined primitive return value from class " \
     "constructor")                                                      \
-  V(harmony_dynamic_import, "harmony dynamic import")                   \
   V(harmony_public_fields, "harmony public fields in class literals")
 
 // Features that are shipping (turned on by default, but internal flag remains).
-#define HARMONY_SHIPPING_BASE(V)                                        \
-  V(harmony_sharedarraybuffer, "harmony sharedarraybuffer")             \
-  V(harmony_regexp_named_captures, "harmony regexp named captures")     \
-  V(harmony_regexp_property, "harmony Unicode regexp property classes") \
-  V(harmony_function_tostring, "harmony Function.prototype.toString")   \
-  V(harmony_promise_finally, "harmony Promise.prototype.finally")       \
-  V(harmony_optional_catch_binding, "allow omitting binding in catch blocks")
+#define HARMONY_SHIPPING_BASE(V)                                              \
+  V(harmony_sharedarraybuffer, "harmony sharedarraybuffer")                   \
+  V(harmony_regexp_named_captures, "harmony regexp named captures")           \
+  V(harmony_regexp_property, "harmony Unicode regexp property classes")       \
+  V(harmony_function_tostring, "harmony Function.prototype.toString")         \
+  V(harmony_promise_finally, "harmony Promise.prototype.finally")             \
+  V(harmony_optional_catch_binding, "allow omitting binding in catch blocks") \
+  V(harmony_import_meta, "harmony import.meta property")                      \
+  V(harmony_dynamic_import, "harmony dynamic import")
 
 #ifdef V8_INTL_SUPPORT
 #define HARMONY_SHIPPING(V)                      \