[build] Also duplicate platform files under root_out_dir temporarily for Golem.

Change-Id: I28f529ea55e678f253cf45f7e3f42a8b63e1e594
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/435260
Reviewed-by: Alexander Aprelev <[email protected]>
Commit-Queue: Ryan Macnak <[email protected]>

Author: rmacnak-google

BUILD.gn

@@ -32,6 +32,18 @@ group("most") {
   ]
 }
 
+# Delete this after Golem moves to vm_platform.dill.
+copy("copy_vm_strong_dill_files") {
+  deps = [ "runtime/vm:kernel_platform_files($host_toolchain)" ]
+  sources = [ "$root_out_dir/vm_platform.dill" ]
+  outputs = [ "$root_out_dir/vm_platform_strong.dill" ]
+}
+copy("copy_vm_strong_outline_files") {
+  deps = [ "runtime/vm:kernel_platform_files($host_toolchain)" ]
+  sources = [ "$root_out_dir/vm_outline.dill" ]
+  outputs = [ "$root_out_dir/vm_outline_strong.dill" ]
+}
+
 group("runtime") {
   import("runtime/runtime_args.gni")
 
@@ -41,6 +53,8 @@ group("runtime") {
   }
 
   deps = [
+    ":copy_vm_strong_dill_files",
+    ":copy_vm_strong_outline_files",
     "runtime/bin:dart",
     "runtime/bin:ffi_test_dynamic_library",
     "runtime/bin:ffi_test_functions",