Fix the New Flutter Project action from hanging (#8390)

This resolves #8310

Author: jwren

src/io/flutter/actions/FlutterNewProjectAction.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2017 The Chromium Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+package io.flutter.actions
+
+import com.intellij.ide.impl.createNewProjectAsync
+import com.intellij.ide.projectWizard.NewProjectWizard
+import com.intellij.openapi.actionSystem.ActionUpdateThread
+import com.intellij.openapi.actionSystem.AnAction
+import com.intellij.openapi.actionSystem.AnActionEvent
+import com.intellij.openapi.application.EDT
+import com.intellij.openapi.project.DumbAware
+import com.intellij.openapi.roots.ui.configuration.ModulesProvider
+import com.intellij.openapi.wm.impl.welcomeScreen.NewWelcomeScreen
+import io.flutter.FlutterBundle
+import io.flutter.FlutterUtils
+import kotlinx.coroutines.DelicateCoroutinesApi
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+
+/**
+ * This classes was re-implemented with Kotlin from FlutterNewProjectAction.java to resolve the New Flutter Project action from hanging,
+ * https://github.com/flutter/flutter-intellij/issues/8310.
+ *
+ * See https://github.com/JetBrains/intellij-community/blob/master/java/idea-ui/src/com/intellij/ide/impl/NewProjectUtil.kt
+ */
+class FlutterNewProjectAction : AnAction(FlutterBundle.message("action.new.project.title")), DumbAware {
+  override fun update(e: AnActionEvent) {
+    if (NewWelcomeScreen.isNewWelcomeScreen(e)) {
+      e.presentation.setText(FlutterBundle.message("welcome.new.project.compact"))
+    }
+  }
+
+  @OptIn(DelicateCoroutinesApi::class)
+  override fun actionPerformed(e: AnActionEvent) {
+    if (FlutterUtils.isAndroidStudio()) {
+      System.setProperty("studio.projectview", "true")
+    }
+
+    GlobalScope.launch {
+      val wizard = withContext(Dispatchers.EDT) {
+        NewProjectWizard(null, ModulesProvider.EMPTY_MODULES_PROVIDER, null)
+      }
+      createNewProjectAsync(wizard)
+    }
+
+  }
+
+  override fun getActionUpdateThread() = ActionUpdateThread.BGT
+}