Reverts "Fix regression in NDK version checking (#166998)" (#167007)

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Reverts: flutter/flutter#166998
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<!-- start_initiating_author -->
Initiated by: gmackall
<!-- end_initiating_author -->
<!-- start_revert_reason -->
Reason for reverting:
https://github.com/flutter/flutter/pull/166998#issuecomment-2798030501
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<!-- start_original_pr_author -->
Original PR Author: gmackall
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Reviewed By: {stuartmorgan-g}
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This change reverts the following previous change:
Fixes a regression from https://github.com/flutter/flutter/pull/166727/,
see
https://discord.com/channels/608014603317936148/846507907876257822/1360306682999210204

Adds a dependency on `shared_preferences_android` to the smoke tests we
have that run across the range of AGP/Gradle versions we support. Chosen
randomly, just to recreate the error. Hopefully this doesn't push the
test target into timeout range, it was already a kind of long running
one.

The IDE suggestion here was misleading, as this value switched from
nullable to non nullable in AGP 8.1/8.2. Unfortunately the IDE makes
these suggestions based on one AGP version, specified in the project
level `build.gradle.kts`. I checked all other files with our minimum
supported AGP version, and this was the only error.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [ ] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [x] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

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Co-authored-by: auto-submit[bot] <flutter-engprod-team@google.com>

dev/devicelab/lib/framework/dependency_smoke_test_task_definition.dart

@@ -144,13 +144,6 @@ Future<TaskResult> buildFlutterApkWithSpecifiedDependencyVersions({
           .replaceFirst(kgpReplacementString, versions.kotlinVersion);
       await gradleSettingsFile.writeAsString(settingsContent, flush: true);
 
-      section('Add a dependency on a plugin');
-      await flutter(
-        'pub',
-        options: <String>['add', 'shared_preferences_android:2.4.9'], // Chosen randomly.
-        workingDirectory: appPath,
-      );
-
       // Ensure that gradle files exists from templates.
       section(
         "Ensure 'flutter build apk' succeeds with Gradle ${versions.gradleVersion}, AGP ${versions.agpVersion}, and Kotlin ${versions.kotlinVersion}",

packages/flutter_tools/gradle/src/main/kotlin/FlutterPluginUtils.kt

@@ -517,16 +517,8 @@ object FlutterPluginUtils {
                 getCompileSdkFromProject(project).toIntOrNull() ?: Int.MAX_VALUE
 
             var maxPluginCompileSdkVersion = projectCompileSdkVersion
-            // TODO(gmackall): This should be updated to reflect newer templates.
-            // The default for AGP 4.1.0 used in old templates.
-            val ndkVersionIfUnspecified = "21.1.6352462"
-
-            // TODO(gmackall): We can remove this elvis when our minimum AGP is >= 8.2.
-            //  This value (ndkVersion) is nullable on AGP versions below that.
-            //  See https://developer.android.com/reference/tools/gradle-api/8.1/com/android/build/api/dsl/CommonExtension#ndkVersion().
-            @Suppress("USELESS_ELVIS")
-            val projectNdkVersion: String =
-                getAndroidExtension(project).ndkVersion // ?: ndkVersionIfUnspecified
+            val projectNdkVersion =
+                getAndroidExtension(project).ndkVersion
             var maxPluginNdkVersion = projectNdkVersion
             var numProcessedPlugins = pluginList.size
             val pluginsWithHigherSdkVersion = mutableListOf<PluginVersionPair>()
@@ -551,13 +543,8 @@ object FlutterPluginUtils {
                             )
                         )
                     }
-
-                    // TODO(gmackall): We can remove this elvis when our minimum AGP is >= 8.2.
-                    //  This value (ndkVersion) is nullable on AGP versions below that.
-                    //  See https://developer.android.com/reference/tools/gradle-api/8.1/com/android/build/api/dsl/CommonExtension#ndkVersion().
-                    @Suppress("USELESS_ELVIS")
                     val pluginNdkVersion: String =
-                        getAndroidExtension(pluginProject).ndkVersion // ?: ndkVersionIfUnspecified
+                        getAndroidExtension(pluginProject).ndkVersion
                     maxPluginNdkVersion =
                         VersionUtils.mostRecentSemanticVersion(
                             pluginNdkVersion,