Bytecode remaining stability

[asotona]

Minor stability fixes of BytecodeGenerator and BytecodeLift

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Progress

• [x] Change must not contain extraneous whitespace

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/babylon.git pull/237/head:pull/237
$ git checkout pull/237

Update a local copy of the PR:
$ git checkout pull/237
$ git pull https://git.openjdk.org/babylon.git pull/237/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 237

View PR using the GUI difftool:
$ git pr show -t 237

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/babylon/pull/237.diff