n-api: take n-api out of experimental

Take n-api out of experimental as per:
nodejs/TSC#501

Backport-PR-URL: #21083
PR-URL: #19262
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>

doc/api/n-api.md

@@ -2,7 +2,7 @@
 
 <!--introduced_in=v7.10.0-->
 
-> Stability: 1 - Experimental
+> Stability: 2 - Stable
 
 N-API (pronounced N as in the letter, followed by API)
 is an API for building native Addons. It is independent from

src/env-inl.h

@@ -318,7 +318,6 @@ inline Environment::Environment(IsolateData* isolate_data,
       printed_error_(false),
       trace_sync_io_(false),
       abort_on_uncaught_exception_(false),
-      emit_napi_warning_(true),
       makecallback_cntr_(0),
       scheduled_immediate_count_(isolate_, 1),
 #if HAVE_INSPECTOR

src/env.cc

@@ -202,12 +202,6 @@ bool Environment::RemovePromiseHook(promise_hook_func fn, void* arg) {
   return true;
 }
 
-bool Environment::EmitNapiWarning() {
-  bool current_value = emit_napi_warning_;
-  emit_napi_warning_ = false;
-  return current_value;
-}
-
 void Environment::EnvPromiseHook(v8::PromiseHookType type,
                                  v8::Local<v8::Promise> promise,
                                  v8::Local<v8::Value> parent) {

src/env.h

@@ -688,7 +688,6 @@ class Environment {
 
   void AddPromiseHook(promise_hook_func fn, void* arg);
   bool RemovePromiseHook(promise_hook_func fn, void* arg);
-  bool EmitNapiWarning();
 
   typedef void (*native_immediate_callback)(Environment* env, void* data);
   // cb will be called as cb(env, data) on the next event loop iteration.
@@ -720,7 +719,6 @@ class Environment {
   bool printed_error_;
   bool trace_sync_io_;
   bool abort_on_uncaught_exception_;
-  bool emit_napi_warning_;
   size_t makecallback_cntr_;
   std::vector<double> destroy_async_id_list_;
 

src/node.cc

@@ -2666,12 +2666,9 @@ static void DLOpen(const FunctionCallbackInfo<Value>& args) {
     env->ThrowError("Module did not self-register.");
     return;
   }
-  if (mp->nm_version == -1) {
-    if (env->EmitNapiWarning()) {
-      ProcessEmitWarning(env, "N-API is an experimental feature and could "
-                         "change at any time.");
-    }
-  } else if (mp->nm_version != NODE_MODULE_VERSION) {
+
+  // -1 is used for N-API modules
+  if ((mp->nm_version != -1) && (mp->nm_version != NODE_MODULE_VERSION)) {
     char errmsg[1024];
     snprintf(errmsg,
              sizeof(errmsg),

src/node_api.cc

@@ -1,13 +1,3 @@
-/******************************************************************************
- * Experimental prototype for demonstrating VM agnostic and ABI stable API
- * for native modules to use instead of using Nan and V8 APIs directly.
- *
- * The current status is "Experimental" and should not be used for
- * production applications.  The API is still subject to change
- * and as an experimental feature is NOT subject to semver.
- *
- ******************************************************************************/
-
 #include <node_buffer.h>
 #include <node_object_wrap.h>
 #include <limits.h>  // INT_MAX

src/node_api.h

@@ -1,12 +1,3 @@
-/******************************************************************************
- * Experimental prototype for demonstrating VM agnostic and ABI stable API
- * for native modules to use instead of using Nan and V8 APIs directly.
- *
- * The current status is "Experimental" and should not be used for
- * production applications.  The API is still subject to change
- * and as an experimental feature is NOT subject to semver.
- *
- ******************************************************************************/
 #ifndef SRC_NODE_API_H_
 #define SRC_NODE_API_H_