Fix module processing after latest Closure changes

New Closure-compiler doesn't add goog.provide/require calls to processed modules:

https://github.com/google/closure-compiler/pull/2641

> ES6 and CommonJS modules no longer generate synthetic goog.require and goog.provide calls.

Currently {process-js-modules} uses {load-library}, which reads the goog.provide calls in the file, to determine the name for processed module, something like {module$absolute$path}.
Now that the file doesn't have goog.provide call, this breaks.

As the module name is based on file-path, we can determine the module name directly from filepath, Closure provides utility for this: {ModuleNames/fileToModuleName}.