Translator: Fix uniform/struct separation for anonymous arrays When a uniform array of anonymous structs was separated into a struct declaration and uniform array, the uniform symbol was being replaced, but not the intermediate nodes that index it. This caused an AST validation error. Bug: angleproject:4740 Change-Id: Ib9d0115bd01c39d1a007f644e46b5e35c12c9304 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3204590 Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Tim Van Patten <timvp@google.com>