ios: add CrNet

ios/build/packaging/dummy_main.mm

Index: ios/build/packaging/dummy_main.mm
diff --git a/tools/clang/blink_gc_plugin/tests/stack_allocated.cpp b/ios/build/packaging/dummy_main.mm
similarity index 62%
copy from tools/clang/blink_gc_plugin/tests/stack_allocated.cpp
copy to ios/build/packaging/dummy_main.mm
index 450b3b50de8343cfbfad06b3b4e0ebecb2edb65b..20dd1ba9897fabfbc3bd480c374e0526dbdfe90d 100644
--- a/tools/clang/blink_gc_plugin/tests/stack_allocated.cpp
+++ b/ios/build/packaging/dummy_main.mm
@@ -2,12 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "stack_allocated.h"
-
-namespace blink {
-
-void HeapObject::trace(Visitor* visitor)
-{
-}
-
+// Provides a main() function for an empty dummy app.
+int main(int argc, char *argv[]) {
+  return 0;
 }