Fix un-expansion of macros when the spacing around its use is changed by translation

[Hackerpilot]

ParameterAwareMacroExpander would capture spaces before macro names - storing it in the string that it uses to later un-expand macros. This would break in cases where the translation tool produced names with more qualifiers than the corresponding input.

Before:

1. input: create [$table]
2. expanded: create actual_table
3. translated: create db.actual_table
4. un-expanded: create db.actual_table

After:

1. input: create [$table]
2. expanded: create actual_table
3. translated: create db.actual_table
4. un-expanded: create db.[$table]

(ParameterAwareMacroExpander should not have modified its input pattern without documenting that it does so)