Fix: Flutter SDK path in settings is not updated (#8827)

The settings page UI for the Flutter SDK path was not updating after
being changed. When a user updated the path, applied the change, and
re-opened settings, the old path would still be displayed.

This was caused by the settings page reading the SDK path from a stale
cache provided by the Dart plugin (FlutterSdk.getFlutterSdk()).

The fix is to use FlutterSdk.getIncomplete() instead, which bypasses the
cache and reads the path directly from the authoritative source: the
project's Library Table configuration. This ensures the UI always
displays the currently configured value.

Fixes: #8641

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---------

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: cj-radcliff

src/io/flutter/sdk/FlutterSettingsConfigurable.java

@@ -1,4 +1,4 @@
-/*
+  /*
  * Copyright 2016 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.
@@ -15,6 +15,7 @@
 import com.intellij.openapi.actionSystem.ActionToolbar;
 import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.application.ModalityState;
+import com.intellij.openapi.application.ReadAction;
 import com.intellij.openapi.fileChooser.FileChooser;
 import com.intellij.openapi.fileChooser.FileChooserDescriptor;
 import com.intellij.openapi.fileChooser.FileChooserDescriptorFactory;
@@ -110,7 +111,7 @@ public class FlutterSettingsConfigurable implements SearchableConfigurable {
   }
 
   private void init() {
-    final FlutterSdk sdk = FlutterSdk.getFlutterSdk(myProject);
+    final FlutterSdk sdk = ReadAction.compute(() -> FlutterSdk.getIncomplete(myProject));
     if (sdk != null) {
       previousSdkVersion = sdk.getVersion();
     }
@@ -185,7 +186,7 @@ public JComponent createComponent() {
   @Override
   public boolean isModified() {
 
-    final FlutterSdk sdk = FlutterSdk.getFlutterSdk(myProject);
+    final FlutterSdk sdk = FlutterSdk.getIncomplete(myProject);
     final FlutterSettings settings = FlutterSettings.getInstance();
     final String sdkPathInModel = sdk == null ? "" : sdk.getHomePath();
     final String sdkPathInUI = FileUtilRt.toSystemIndependentName(getSdkPathText());
@@ -312,7 +313,7 @@ public void apply() throws ConfigurationException {
 
   @Override
   public void reset() {
-    final FlutterSdk sdk = FlutterSdk.getFlutterSdk(myProject);
+    final FlutterSdk sdk = ReadAction.compute(() -> FlutterSdk.getIncomplete(myProject));
     final String path = sdk != null ? sdk.getHomePath() : "";
 
     // Set this after populating the combo box to display correctly when the Flutter SDK is unset.