Issue #3104307 by Berdir, longwave, Gábor Hojtsy, Wim Leers, alexpott, andypost: Remove  BC layers in various Drupal\Core components

Issue #2904550 by tim.plunkett, Sam152, jwilson3, neclimdul, eelkeblok, amateescu, DuaelFr, K3vin_nl, alexpott, tedbow, andypost: PluginDependencyTrait::calculatePluginDependencies() does not handle theme provided plugins

Issue #2939925 by jibran, tim.plunkett, yo30: Add a getPluginDependencies() method to \Drupal\Core\Plugin\PluginDependencyTrait

Issue #2851574 by tim.plunkett, mpdonadio: DependentPluginDefinitionInterface and DependentPluginDefinitionTrait should be in Drupal\Core not Drupal\Component

Issue #2821191 by tim.plunkett, tstoeckler, jibran: Allow object-based plugin definitions to be processed in PluginDependencyTrait

Issue #2665992 by alexpott, klausi, heykarthikwithu, xjm, tstoeckler: @file is not required for classes, interfaces and traits

Issue #2271419 by alexpott, larowlan: Fixed Allow field types, widgets, formatters to specify config dependencies.

Issue #2266859 by tim.plunkett: Move the dependency calculation helper methods from ConfigEntityBase to generic traits.