[FIR] Don't create DNN types for flexible simple types

^KT-50788

compiler/fir/analysis-tests/testData/resolve/inference/dnnThrowJavaCall.fir.txt

@@ -0,0 +1,4 @@
+FILE: main.kt
+    public final fun getExcludedDirs(project: R|Project|, excludedProjects: R|kotlin/collections/List<Project>|): R|kotlin/collections/List<java/io/File>| {
+        ^getExcludedDirs R|<local>/project|.R|/Project.plugins|.R|/PluginContainer.findPlugin|<R|ft<IdeaPlugin, IdeaPlugin?>|>(<getClass>(Q|IdeaPlugin|).R|kotlin/jvm/java|<R|IdeaPlugin|>)?.{ $subj$.R|/IdeaPlugin.excludeDirs| }?.{ $subj$.R|kotlin/collections/toList|<R|ft<java/io/File, java/io/File?>|>() } ?: R|kotlin/collections/emptyList|<R|java/io/File|>()
+    }

compiler/fir/analysis-tests/testData/resolve/inference/dnnThrowJavaCall.kt

@@ -0,0 +1,37 @@
+// WITH_STDLIB
+// FULL_JDK
+
+// FILE: Plugin.java
+public interface Plugin {}
+
+// FILE: IdeaPlugin.java
+import java.io.File
+import java.util.Set
+
+public interface IdeaPlugin extends Plugin {
+    Set<File> getExcludeDirs()
+}
+
+// FILE: PluginContainer.java
+import javax.annotation.Nullable
+
+public interface PluginContainer {
+    @Nullable
+    <T extends Plugin> T findPlugin(Class<T> type);
+}
+
+// FILE: Project.java
+public interface Project {
+    PluginContainer getPlugins();
+
+    Project getRootProject();
+
+    File getBuildDir();
+}
+
+// FILE: main.kt
+import java.io.File
+
+fun getExcludedDirs(project: Project, excludedProjects: List<Project>): List<File> {
+    return project.plugins.findPlugin(IdeaPlugin::class.java)?.excludeDirs?.toList() ?: emptyList()
+}