DevTools: Implement module dependencies loading in ModuleManager

This allows to dynamically load modules that, in turn, have dependencies
that should be loaded dynamically.

The "codemirror" and "resource_views" modules have been merged into
"source_frame", and the "workers" has been removed.

R=pfeldman@chromium.org, pfeldman

Review URL: https://codereview.chromium.org/255713003

git-svn-id: svn://svn.chromium.org/blink/trunk@172640 bbb929c8-8fbe-4397-9dbb-9b2b20218538