Fixed bug where PlzNavigate CSP in a iframe did not get the inherited CSP

When inheriting the CSP from a parent document to a local-scheme CSP,
it does not always get propagated to the PlzNavigate CSP. This means
that PlzNavigate CSP checks (like `frame-src`) would be ran against
a blank policy instead of the proper inherited policy.

Bug: 778658
Change-Id: I61bb0d432e1cea52f199e855624cb7b3078f56a9
Reviewed-on: https://chromium-review.googlesource.com/765969
Commit-Queue: Andy Paicu <andypaicu@chromium.org>
Reviewed-by: Mike West <mkwst@chromium.org>
Cr-Commit-Position: refs/heads/master@{#518245}
void Document::Trace(blink::Visitor* visitor) {
  visitor->Trace(imports_controller_);
  visitor->Trace(doc_type_);
  visitor->Trace(implementation_);
  visitor->Trace(autofocus_element_);
  visitor->Trace(focused_element_);
  visitor->Trace(sequential_focus_navigation_starting_point_);
  visitor->Trace(hover_element_);
  visitor->Trace(active_element_);
  visitor->Trace(document_element_);
  visitor->Trace(root_scroller_controller_);
  visitor->Trace(title_element_);
  visitor->Trace(ax_object_cache_);
  visitor->Trace(markers_);
  visitor->Trace(css_target_);
  visitor->Trace(current_script_stack_);
  visitor->Trace(script_runner_);
  visitor->Trace(lists_invalidated_at_document_);
  visitor->Trace(node_lists_);
  visitor->Trace(top_layer_elements_);
  visitor->Trace(elem_sheet_);
  visitor->Trace(node_iterators_);
  visitor->Trace(ranges_);
  visitor->Trace(style_engine_);
  visitor->Trace(form_controller_);
  visitor->Trace(visited_link_state_);
  visitor->Trace(frame_);
  visitor->Trace(dom_window_);
  visitor->Trace(fetcher_);
  visitor->Trace(parser_);
  visitor->Trace(context_features_);
  visitor->Trace(style_sheet_list_);
  visitor->Trace(document_timing_);
  visitor->Trace(media_query_matcher_);
  visitor->Trace(scripted_animation_controller_);
  visitor->Trace(scripted_idle_task_controller_);
  visitor->Trace(text_autosizer_);
  visitor->Trace(registration_context_);
  visitor->Trace(custom_element_microtask_run_queue_);
  visitor->Trace(element_data_cache_);
  visitor->Trace(use_elements_needing_update_);
  visitor->Trace(timers_);
  visitor->Trace(template_document_);
  visitor->Trace(template_document_host_);
  visitor->Trace(user_action_elements_);
  visitor->Trace(svg_extensions_);
  visitor->Trace(timeline_);
  visitor->Trace(pending_animations_);
  visitor->Trace(worklet_animation_controller_);
  visitor->Trace(context_document_);
  visitor->Trace(canvas_font_cache_);
  visitor->Trace(intersection_observer_controller_);
  visitor->Trace(snap_coordinator_);
  visitor->Trace(resize_observer_controller_);
  visitor->Trace(property_registry_);
  visitor->Trace(network_state_observer_);
  Supplementable<Document>::Trace(visitor);
  TreeScope::Trace(visitor);
  ContainerNode::Trace(visitor);
  ExecutionContext::Trace(visitor);
  SecurityContext::Trace(visitor);
  DocumentShutdownNotifier::Trace(visitor);
  SynchronousMutationNotifier::Trace(visitor);
}

void Document::Trace(blink::Visitor* visitor) {
  visitor->Trace(imports_controller_);
  visitor->Trace(doc_type_);
  visitor->Trace(implementation_);
  visitor->Trace(autofocus_element_);
  visitor->Trace(focused_element_);
  visitor->Trace(sequential_focus_navigation_starting_point_);
  visitor->Trace(hover_element_);
  visitor->Trace(active_element_);
  visitor->Trace(document_element_);
  visitor->Trace(root_scroller_controller_);
  visitor->Trace(title_element_);
  visitor->Trace(ax_object_cache_);
  visitor->Trace(markers_);
  visitor->Trace(css_target_);
  visitor->Trace(current_script_stack_);
  visitor->Trace(script_runner_);
  visitor->Trace(lists_invalidated_at_document_);
  visitor->Trace(node_lists_);
  visitor->Trace(top_layer_elements_);
  visitor->Trace(elem_sheet_);
  visitor->Trace(node_iterators_);
  visitor->Trace(ranges_);
  visitor->Trace(style_engine_);
  visitor->Trace(form_controller_);
  visitor->Trace(visited_link_state_);
  visitor->Trace(frame_);
  visitor->Trace(dom_window_);
  visitor->Trace(fetcher_);
  visitor->Trace(parser_);
  visitor->Trace(context_features_);
  visitor->Trace(style_sheet_list_);
  visitor->Trace(document_timing_);
  visitor->Trace(media_query_matcher_);
  visitor->Trace(scripted_animation_controller_);
  visitor->Trace(scripted_idle_task_controller_);
  visitor->Trace(text_autosizer_);
  visitor->Trace(registration_context_);
  visitor->Trace(custom_element_microtask_run_queue_);
  visitor->Trace(element_data_cache_);
  visitor->Trace(use_elements_needing_update_);
  visitor->Trace(timers_);
  visitor->Trace(template_document_);
  visitor->Trace(template_document_host_);
  visitor->Trace(user_action_elements_);
  visitor->Trace(svg_extensions_);
  visitor->Trace(timeline_);
  visitor->Trace(pending_animations_);
  visitor->Trace(worklet_animation_controller_);
  visitor->Trace(context_document_);
  visitor->Trace(canvas_font_cache_);
  visitor->Trace(intersection_observer_controller_);
  visitor->Trace(snap_coordinator_);
  visitor->Trace(resize_observer_controller_);
  visitor->Trace(property_registry_);
  visitor->Trace(network_state_observer_);
  Supplementable<Document>::Trace(visitor);
  TreeScope::Trace(visitor);
  ContainerNode::Trace(visitor);
  ExecutionContext::Trace(visitor);
  SecurityContext::Trace(visitor);
  DocumentShutdownNotifier::Trace(visitor);
  SynchronousMutationNotifier::Trace(visitor);
}
