Bump Android Compile SDK to 31 (flutter#92022)

Author: Emmanuel Garcia

dev/integration_tests/gradle_deprecated_settings/android/app/build.gradle

@@ -19,7 +19,8 @@ apply plugin: 'com.android.application'
 apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
 
 android {
-    compileSdkVersion flutter.compileSdkVersion
+    // TODO(egarciad): Bump once https://github.com/flutter/flutter/issues/89578 is fixed.
+    compileSdkVersion 30
 
     compileOptions {
         sourceCompatibility JavaVersion.VERSION_1_8

packages/flutter_tools/gradle/flutter.gradle

@@ -30,7 +30,7 @@ import org.gradle.util.VersionNumber
 /** For apps only. Provides the flutter extension used in app/build.gradle. */
 class FlutterExtension {
     /** Sets the compileSdkVersion used by default in Flutter app projects. */
-    static int compileSdkVersion = 30
+    static int compileSdkVersion = 31
 
     /** Sets the minSdkVersion used by default in Flutter app projects. */
     static int minSdkVersion = 16