For structs, we were already loading the size of the struct at
runtime for the size of the memcopy. This CL makes that work for
the `Array`s as well.
TEST=pkg/vm/testcases/transformations/ffi/regress_62087.dart
TEST=tests/ffi/native_assets/asset_absolute_test.dart
Closes: https://github.com/dart-lang/sdk/issues/62087
Change-Id: I15a5796d713879a613971e080d18101111704b9b
Cq-Include-Trybots: dart/try:vm-aot-linux-debug-arm64-try,vm-aot-linux-debug-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-mac-debug-arm64-try,vm-aot-mac-debug-x64-try,vm-aot-obfuscate-linux-release-x64-try,vm-aot-optimization-level-linux-release-x64-try,vm-aot-win-debug-arm64-try,vm-aot-win-debug-x64-try,vm-aot-win-debug-x64c-try,vm-asan-linux-release-arm64-try,vm-asan-linux-release-x64-try,vm-asan-mac-release-arm64-try,vm-asan-win-release-x64-try,vm-dyn-linux-debug-x64-try,vm-dyn-mac-debug-arm64-try,vm-ffi-dyn-mac-debug-simarm64_arm64-try,vm-msan-linux-release-arm64-try,vm-msan-linux-release-x64-try,vm-tsan-linux-release-arm64-try,vm-tsan-linux-release-x64-try,vm-tsan-mac-release-arm64-try,vm-ubsan-linux-release-arm64-try,vm-ubsan-linux-release-x64-try,vm-ubsan-mac-release-arm64-try,vm-ubsan-win-release-x64-try
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/464706
Reviewed-by: Tess Strickland <sstrickl@google.com>
Reviewed-by: Michael Goderbauer <goderbauer@google.com>
Daco Harkes
b277407152