Subzero: Shorten global prefixes in non-DUMP build.

Reverts part of 843142fe (https://codereview.chromium.org/1776343004).

Makes global prefixes short in all non-DUMP builds, not just the browser
build, so that the user doesn't need to remember to supply the override
options in a command-line MINIMAL build.

BUG= none
R=jpp@chromium.org

Review URL: https://codereview.chromium.org/1805593002 .