Add v8::Promise::Then.

src/api.cc

 // 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.
 
 #include "api.h"
 
 #include <string.h>  // For memcpy, strlen.
 #ifdef V8_USE_ADDRESS_SANITIZER
 #include <sanitizer/asan_interface.h>
 #endif  // V8_USE_ADDRESS_SANITIZER
@@ skipping 5892 matching lines @@
       handle(isolate->context()->global_object()->native_context()->
              promise_catch()),
       promise,
       ARRAY_SIZE(argv), argv,
       false).ToHandle(&result);
   EXCEPTION_BAILOUT_CHECK(isolate, Local<Promise>());
   return Local<Promise>::Cast(Utils::ToLocal(result));
 }
 
 
+Local<Promise> Promise::Then(Handle<Function> handler) {
+  i::Handle<i::JSObject> promise = Utils::OpenHandle(this);
+  i::Isolate* isolate = promise->GetIsolate();
+  LOG_API(isolate, "Promise::Then");
+  ENTER_V8(isolate);
+  EXCEPTION_PREAMBLE(isolate);
+  i::Handle<i::Object> argv[] = { Utils::OpenHandle(*handler) };
+  i::Handle<i::Object> result;
+  has_pending_exception = !i::Execution::Call(
+      isolate,
+      handle(isolate->context()->global_object()->native_context()->
+             promise_then()),
+      promise,
+      ARRAY_SIZE(argv), argv,
+      false).ToHandle(&result);
+  EXCEPTION_BAILOUT_CHECK(isolate, Local<Promise>());
+  return Local<Promise>::Cast(Utils::ToLocal(result));
+}
+
+
 bool v8::ArrayBuffer::IsExternal() const {
   return Utils::OpenHandle(this)->is_external();
 }
 
 
 v8::ArrayBuffer::Contents v8::ArrayBuffer::Externalize() {
   i::Handle<i::JSArrayBuffer> obj = Utils::OpenHandle(this);
   Utils::ApiCheck(!obj->is_external(),
                   "v8::ArrayBuffer::Externalize",
                   "ArrayBuffer already externalized");
@@ skipping 1643 matching lines @@
   Isolate* isolate = reinterpret_cast<Isolate*>(info.GetIsolate());
   Address callback_address =
       reinterpret_cast<Address>(reinterpret_cast<intptr_t>(callback));
   VMState<EXTERNAL> state(isolate);
   ExternalCallbackScope call_scope(isolate, callback_address);
   callback(info);
 }
 
 
 } }  // namespace v8::internal