[Extensions Bindings] Move directory util out of runtime_custom_bindings
The chrome.runtime API has a method called `getPackageDirectoryEntry`
which has custom bindings to retrieve the app's directory entry (a la
HTML5 filesystem) and return it. The custom bindings for this are
quite strange, since it needs to be done from the app's background
page.
Move this to the file_entry_binding_util.js file, where the similar
getFileBindingsForApi() function is implemented. In addition to grouping
similar logic, this solves a native bindings issue where with trying to
require an API directly (which is disallowed).
BUG=653596
TBR=michaelpg@chromium.org (moving a resource)
Review-Url: https://codereview.chromium.org/2895493004
Cr-Commit-Position: refs/heads/master@{#473977}
6 files changed
