By default, the Sprockets DirectiveProcessor introduces a newline between possible 'header' comments and the rest of the JS file. This causes sourcemaps to be offset by 1 line, and therefore breaks browser tooling. We know that Ember-Cli assets do not use Sprockets directives, so we can totally bypass the DirectiveProcessor for those files.
We're using v3 of Sprockets, which is no longer supported - upstreaming a fix will be difficult. Long term, we intend to move away from sprockets.
This patch removes some of our freedom patches that have been deprecated
for some time now.
Some of them have been updated so we’re not shipping code based on an
old version of Rails.
When plugin spec is evaluated for the first time, it took 30 seconds to run:
```
rm -rf tmp/* && LOAD_PLUGINS=1 be rspec ./plugins/discourse-solved/spec/requests/topics_controller_spec.rb
```
Applying sprocket patch in test environment solves that issue
This reduces chances of errors where consumers of strings mutate inputs
and reduces memory usage of the app.
Test suite passes now, but there may be some stuff left, so we will run
a few sites on a branch prior to merging