Metal: Remove uniform struct decl separation code Remove uniform specific struct declaration separation and anonymous struct naming code. This is already done by SeparateDeclarations. Removes code for NameEmbeddedUniformStructsMetal. Does not remove SeparateStructFromUniformDeclarations code as it is used for SPIRV. Bug: angleproject:375937551 Change-Id: I943d96897d97b23fd0f54155dc215a4490f63937 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5972994 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Commit-Queue: Kimmo Kinnunen <kkinnunen@apple.com>