This only changes iterator type specifiers and cast expressions.

See
https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-auto.html
for more on this warning.

Bug: v8:10488
Change-Id: I26b4f837524c640021e44f39315201173b5867f1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2191348Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67813}