Contextual analysis: Counting local variables in copied render contexts

[jg-rp]

We currently fail to count assign, capture, decrement and increment variables that appear in copied render contexts (like those used with {% render %}, for example).

When calling analyze_with_context() on bar.liquid below, we count other twice in all_variables and once in undefined_variables, but other does not appear in local_variables. Counting other as a local variable from line 1 of foo.liquid is probably more useful.

foo.liquid

{% assign other = 42 %}
{{ other }}

bar.liquid

{% assign some = 7 %}
{% render "foo.liquid" %}
{{ other }}