Use quota manager to calculate "active project storage used".

The 'active_project_storage_used' method is used to report "how much
of the storage allowance for the given project submission has been
used."

(The name suggests that this is somehow similar to
'published_project_storage_used', but this is not the case: *that*
method is used to inform visitors "how large will the project files be
if I download all of them", which is only tangentially related to the
resource usage that a particular submission is responsible for.)

Reporting (as well as limiting) resource usage is the task of the
QuotaManager.  Use the QuotaManager API and remove the redundant
ProjectFiles API.

physionet-django/project/modelcomponents/activeproject.py

@@ -220,7 +220,7 @@ def storage_used(self):
  versions of this CoreProject. (The QuotaManager should ensure
  that the same file is not counted twice in this total.)
  """
- current = self.files.active_project_storage_used(self)
+ current = self.quota_manager().bytes_used
  published = self.core_project.total_published_size
 
  return current + published

physionet-django/project/projectfiles/base.py

@@ -114,11 +114,6 @@ def project_quota_manager(self, project):
  """Create a quota manager for a project."""
  raise NotImplementedError
 
- @abc.abstractmethod
- def active_project_storage_used(self, project):
- """Total storage used in bytes - active project."""
- raise NotImplementedError
-
  @abc.abstractmethod
  def published_project_storage_used(self, project):
  """Total storage used in bytes - published project."""

physionet-django/project/projectfiles/gcs.py

@@ -137,9 +137,6 @@ def project_quota_manager(self, project):
  quota_manager.set_limits(bytes_hard=limit, bytes_soft=limit)
  return quota_manager
 
- def active_project_storage_used(self, project):
- return self._storage_used(project)
-
  def published_project_storage_used(self, project):
  return self._storage_used(project)
 

physionet-django/project/projectfiles/local.py

@@ -147,9 +147,6 @@ def project_quota_manager(self, project):
  quota_manager.set_limits(bytes_hard=limit, bytes_soft=limit)
  return quota_manager
 
- def active_project_storage_used(self, project):
- return project.quota_manager().bytes_used
-
  def published_project_storage_used(self, project):
  return get_tree_size(project.file_root())