This allows `render_in` components that compile their own templates to
use their view context's current output buffer while a
`with_output_buffer` block is being evaluated.
Partially addresses #39377.
This commit removes a deprecated catch-all route in the AV tests. It
defines and includes the necessary routes for each test such that we
don't need the catch-all anymore.
This also helps push us toward #33970
Erubi offers the following advantages for Rails:
* Works with ruby's --enable-frozen-string-literal option
* Has 88% smaller memory footprint
* Does no freedom patching (Erubis adds a method to Kernel)
* Has simpler internals (1 file, <150 lines of code)
* Has an open development model (Erubis doesn't have a
public source control repository or bug tracker)
* Is not dead (Erubis hasn't been updated since 2011)
Erubi is a simplified fork of Erubis that contains just the
parts that are generally needed (which includes the parts
that Rails uses). The only intentional difference in
behavior is that it does not include support for <%=== tags
for debug output. That could be added to the ActionView ERB
handler if it is desired.
The Erubis template handler remains in a deprecated state
so that code that accesses it directly does not break. It
can be removed after Rails 5.1.
