Let the Kernel FE know whether it's building for a release VM. (#18876)

Fixes #18829

packages/flutter_tools/lib/src/base/build.dart

@@ -391,6 +391,7 @@ class AOTSnapshotter {
       aot: true,
       entryPointsJsonFiles: entryPointsJsonFiles,
       trackWidgetCreation: false,
+      targetProductVm: buildMode == BuildMode.release,
     );
 
     // Write path to frontend_server, since things need to be re-generated when that changes.

packages/flutter_tools/lib/src/compile.dart

@@ -84,6 +84,7 @@ class KernelCompiler {
     String packagesPath,
     List<String> fileSystemRoots,
     String fileSystemScheme,
+    bool targetProductVm = false,
   }) async {
     final String frontendServer = artifacts.getArtifactPath(
       Artifact.frontendServerSnapshotForEngineDartSdk
@@ -134,6 +135,9 @@ class KernelCompiler {
       command.add('--aot');
       command.add('--tfa');
     }
+    if (targetProductVm) {
+      command.add('-Ddart.vm.product=true');
+    }
     if (entryPointsJsonFiles != null) {
       for (String entryPointsJson in entryPointsJsonFiles) {
         command.addAll(<String>['--entry-points', entryPointsJson]);