Stop using CertStore which is not compatible with PlzNavigate.

content/browser/loader/DEPS

 # The core loading code in this directory is being transitioned into a separate
 # Mojo networking service. See http://crbug.com/598073. The first stage is to
 # decouple the code that will be moved from the rest of content. These rules
 # help ensure that we don't add more includes, and can progressively reduce the
 # code's dependencies.
 #
 # For each file, the first section shows includes that are allowed (i.e. because
 # they are for files that will be moving as well). The second section, separated
 # by a comment, lists files that we will have to decouple.
 specific_include_rules = {
@@ skipping 112 matching lines @@
     "+content/public/browser/browser_thread.h",  # Only for DCHECK.
     "+content/public/common/resource_devtools_info.h",
   ],
   "power_save_block_resource_throttle\.(cc|h)": [
     "-content",
     "+content/browser/loader/power_save_block_resource_throttle.h",
     "+content/public/browser/resource_throttle.h",
   ],
   "resource_dispatcher_host_impl\.(cc|h)": [
     "-content",
-    "+content/browser/cert_store_impl.h",
     "+content/browser/loader/async_resource_handler.h",
     "+content/browser/loader/async_revalidation_manager.h",
     "+content/browser/loader/global_routing_id.h",
     "+content/browser/loader/loader_delegate.h",
     "+content/browser/loader/mojo_async_resource_handler.h",
     "+content/browser/loader/power_save_block_resource_throttle.h",
     "+content/browser/loader/resource_dispatcher_host_impl.h",
     "+content/browser/loader/resource_loader.h",
     "+content/browser/loader/resource_loader_delegate.h",
     "+content/browser/loader/resource_message_filter.h",
@@ skipping 69 matching lines @@
   ],
   "resource_loader\.(cc|h)": [
     "-content",
     "+content/browser/loader/resource_handler.h",
     "+content/browser/loader/resource_loader.h",
     "+content/browser/loader/resource_loader_delegate.h",
     "+content/browser/loader/resource_request_info_impl.h",
     "+content/browser/ssl/ssl_client_auth_handler.h",
     "+content/browser/ssl/ssl_error_handler.h",
     "+content/common/content_export.h",
-    "+content/public/browser/cert_store.h",
     "+content/public/browser/resource_controller.h",
     "+content/public/browser/resource_dispatcher_host_login_delegate.h",
     "+content/public/common/resource_response.h",
     "+content/public/common/resource_type.h",
 
     # TODO: these all have to be removed.
     "+content/browser/appcache/appcache_interceptor.h",
     "+content/browser/child_process_security_policy_impl.h",
     "+content/browser/loader/cross_site_resource_handler.h",
     "+content/browser/loader/detachable_resource_handler.h",
@@ skipping 102 matching lines @@
     "+content/common/url_loader.mojom.h",
     "+content/common/url_loader_factory.mojom.h",
     "+content/public/browser/resource_context.h",
     "+content/public/browser/resource_dispatcher_host_delegate.h",
     "+content/public/common/content_paths.h",
     "+content/public/common/process_type.h",
     "+content/public/test/test_browser_context.h",
     "+content/public/test/test_browser_thread_bundle.h",
   ],
 }