Modernize Phriction ordering/paging

Summary: Ref T7803. Fixes T7809. Move Phriction away from getReversePaging() / getPagingColumn().

Test Plan: Paged "All Documents", "Updated", and viewed document hierarchy.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: ite-klass, epriestley

Maniphest Tasks: T7809, T7803

Differential Revision: https://secure.phabricator.com/D12360

src/infrastructure/query/policy/PhabricatorCursorPagedPolicyAwareQuery.php

@@ -249,6 +249,8 @@ abstract class PhabricatorCursorPagedPolicyAwareQuery
       ->setViewer($this->getPagingViewer())
       ->withIDs(array((int)$cursor));
 
+    $this->willExecuteCursorQuery($query);
+
     $object = $query->executeOne();
     if (!$object) {
       throw new Exception(
@@ -260,6 +262,11 @@ abstract class PhabricatorCursorPagedPolicyAwareQuery
     return $object;
   }
 
+  protected function willExecuteCursorQuery(
+    PhabricatorCursorPagedPolicyAwareQuery $query) {
+    return;
+  }
+
 
   /**
    * Simplifies the task of constructing a paging clause across multiple
@@ -446,7 +453,7 @@ abstract class PhabricatorCursorPagedPolicyAwareQuery
   /**
    * @task order
    */
-  private function getOrderVector() {
+  protected function getOrderVector() {
     if (!$this->orderVector) {
       $vector = $this->getDefaultOrderVector();
       $vector = PhabricatorQueryOrderVector::newFromVector($vector);