Reapply "chore: bump flutter version"

mod: disable impeller, ref Kazumi

This reverts commit fe2b4f6735.

android/build.gradle

@@ -16,6 +16,14 @@ allprojects {
 rootProject.buildDir = '../build'
 subprojects {
     afterEvaluate { project ->
+    if (project.hasProperty('android')) {
+        project.android {
+            if (namespace == null) {
+                namespace project.group
+            }
+        }
+    }
+
         if (project.extensions.findByName("android") != null) {
             Integer pluginCompileSdk = project.android.compileSdk
             if (pluginCompileSdk != null && pluginCompileSdk < 31) {