Add base::to_address() to blink's base allow list.

base::to_address() is implemented in base/types/to_address.h, which is
reasonably self-contained, pulling in only STL headers.

This allows the idiom base::to_address(base::span<T>::end()) to be used
in the future to avoid unsafe pointer arithmetic in blink modules.

Change-Id: Ia714a87e8d6b131f219d8ab22f116a6e83c59f71
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6333503
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1429069}