Vulkan: Fix SPIR-V gen for constant constructors ... inside non-constant constructors of different basic type. The SPIR-V generator proactively casts the elements of the inner constructor to the type of the outer constructor, but it was mistakenly using the original inner constructor's type id for the constant instead of the cast type id. Bug: chromium:413775106 Change-Id: I95e8b1dcc1ba36777eb4475042f0d106a6abe109 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/6489041 Reviewed-by: Cody Northrop <cnorthrop@google.com> Reviewed-by: Amirali Abdolrashidi <abdolrashidi@google.com>