initializer react_rails.setup_vendor fails if gem source files were read-only

[jonswar]

These lines in rails/railtie.rb:

    FileUtils.cp(::React::Source.bundled_path_for(filename),
                 tmp_path.join('react.js'))
    FileUtils.cp(::React::Source.bundled_path_for('JSXTransformer.js'),
                 tmp_path.join('JSXTransformer.js'))

will, the first time, create read-only files if the gem sources themselves are read-only (as they are on some deployed systems). On subsequent runs, the copy will fail, causing the initializer to error out. This code should either chmod the files or not copy them if they are already there.

[danielrhodes]

@jonswar Having the same issue. I'll make a PR and see if the chmod works.

[vegetabill]

Just noticed we still have some hacks in our Rails env file to workaround this. @danielrhodes did you ever have a chance to work on a PR for this? If not, I could take a look.

[danielrhodes]

@RearAdmiral Yep done. Didn't do anything fancy. Has been working for a couple months in production.

[vegetabill]

Awesome. Thanks

[rmosolgo]

Good news: #254 please give it a try!