Rationale: java is an optional OS X component, so don't try to build
with Java by default.
Nothing in core uses the java components.
ClosesHomebrew/homebrew#14411.
Way back in the day, Homebrew defaulted to LLVM/-O3. A lot of stuff
failed to compile, and a lot of stuff just took forever with -O4.
We don't default this way anymore, and in fact use -Os per Apple
guidelines.
So remove these old "fixes" since they are no longer needed.
brewkit.rb changes ENV destructively, so lets not do that everytime a formula
is required. Now it's possible for other tools to require a formula
description without worrying about side-effects.