[gardening] Fix gcc build of samples/embedder

GCC doesn't like // comments which are not terminated due to \ at
the end of line.

TEST=ci

Change-Id: I9d6188bf1db9358804b488d73bef88ba5e6b4f39
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/417220
Commit-Queue: Alexander Markov <[email protected]>
Reviewed-by: Tess Strickland <[email protected]>

Author: alexmarkov

pkg/vm/tool/generate_entry_point_shims.dart

@@ -112,18 +112,20 @@ void main(List<String> args) async {
 
   for (final buffer in [declarations, definitions]) {
     buffer.write('''
-// Generated with:
-//   dart pkg/vm/tools/generate_entry_point_shims.dart \\
-//       ''');
+/*
+   Generated with:
+     dart pkg/vm/tool/generate_entry_point_shims.dart \\
+         ''');
     if (createUninitializedInstanceMethods) {
       buffer.write('-u ');
     }
     if (uriString != null) {
       buffer.write('''-p $uriString \\
-//       ''');
+         ''');
     }
     buffer.writeln('''$source \\
-//       $outputPath
+         $outputPath
+*/
 ''');
   }
 

samples/embedder/timer.cc

@@ -1,11 +1,13 @@
 // Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
-//
-// Generated with:
-//   dart pkg/vm/tools/generate_entry_point_shims.dart \
-//       out/ReleaseX64/gen/samples/embedder/timer_aot.dart.dill \
-//       samples/embedder/timer
+
+/*
+   Generated with:
+     dart pkg/vm/tool/generate_entry_point_shims.dart \
+         out/ReleaseX64/gen/samples/embedder/timer_aot.dart.dill \
+         samples/embedder/timer
+*/
 
 #include "timer.h"
 

samples/embedder/timer.h

@@ -1,11 +1,13 @@
 // Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
-//
-// Generated with:
-//   dart pkg/vm/tools/generate_entry_point_shims.dart \
-//       out/ReleaseX64/gen/samples/embedder/timer_aot.dart.dill \
-//       samples/embedder/timer
+
+/*
+   Generated with:
+     dart pkg/vm/tool/generate_entry_point_shims.dart \
+         out/ReleaseX64/gen/samples/embedder/timer_aot.dart.dill \
+         samples/embedder/timer
+*/
 
 #ifndef SAMPLES_EMBEDDER_TIMER_H
 #define SAMPLES_EMBEDDER_TIMER_H