[lldb] Store *signed* ranges in lldb_private::Block (#120224)

This is to support functions whose entry points aren't their lowest
address

(https://discourse.llvm.org/t/rfcish-support-for-discontinuous-functions/83244).
The alternative is to keep blocks relative to the lowest address, but
then introduce a separate concept for the function entry point, which I
think would be more confusing.

This patch just changes the type signedness, it doesn't create any
negative offsets yet. Since combining values with different signs can
sometimes produce unexpected results, and since this is the first use of
RangeVector with a signed type, I'm adding a test to verify that at
least the core functionality works correctly.

0 files changed, 0 insertions, 0 deletions