In Differential, make the "Open in Editor" keystroke work with no selection, or a change or inline selected

Summary:
Ref T13515. Currently, "Open in Editor" only works with a file-level selection.

  - If we have a change-level or inline-level selection, open the parent changeset.
  - If we have no selection, but the banner is showing something, open the fine shown in the banner.

Test Plan: With files, inlines, changes, and no selection, pressed "\". Saw files pop open in my external editor.

Maniphest Tasks: T13515

Differential Revision: https://secure.phabricator.com/D21148

resources/celerity/map.php

@@ -12,7 +12,7 @@ return array(
     'core.pkg.css' => 'a4a2417c',
     'core.pkg.js' => '4355a8d3',
     'differential.pkg.css' => '607c84be',
-    'differential.pkg.js' => 'ececaeef',
+    'differential.pkg.js' => '1a72918e',
     'diffusion.pkg.css' => '42c75c37',
     'diffusion.pkg.js' => 'a98c0bf7',
     'maniphest.pkg.css' => '35995d6d',
@@ -378,7 +378,7 @@ return array(
     'rsrc/js/application/dashboard/behavior-dashboard-query-panel-select.js' => '1e413dc9',
     'rsrc/js/application/dashboard/behavior-dashboard-tab-panel.js' => '0116d3e8',
     'rsrc/js/application/diff/DiffChangeset.js' => '5a4e4a3b',
-    'rsrc/js/application/diff/DiffChangesetList.js' => 'f813ef26',
+    'rsrc/js/application/diff/DiffChangesetList.js' => '139299d7',
     'rsrc/js/application/diff/DiffInline.js' => '16e97ebc',
     'rsrc/js/application/diff/behavior-preview-link.js' => 'f51e9c17',
     'rsrc/js/application/differential/behavior-diff-radios.js' => '925fe8cd',
@@ -775,7 +775,7 @@ return array(
     'phabricator-darkmessage' => '26cd4b73',
     'phabricator-dashboard-css' => '5a205b9d',
     'phabricator-diff-changeset' => '5a4e4a3b',
-    'phabricator-diff-changeset-list' => 'f813ef26',
+    'phabricator-diff-changeset-list' => '139299d7',
     'phabricator-diff-inline' => '16e97ebc',
     'phabricator-drag-and-drop-file-upload' => '4370900d',
     'phabricator-draggable-list' => '0169e425',
@@ -1023,6 +1023,10 @@ return array(
       'javelin-uri',
       'phabricator-keyboard-shortcut',
     ),
+    '139299d7' => array(
+      'javelin-install',
+      'phuix-button-view',
+    ),
     '139ef688' => array(
       'javelin-behavior',
       'javelin-dom',
@@ -2166,10 +2170,6 @@ return array(
       'javelin-stratcom',
       'javelin-dom',
     ),
-    'f813ef26' => array(
-      'javelin-install',
-      'phuix-button-view',
-    ),
     'f84bcbf4' => array(
       'javelin-behavior',
       'javelin-stratcom',

webroot/rsrc/js/application/diff/DiffChangesetList.js

@@ -462,23 +462,28 @@ JX.install('DiffChangesetList', {
       var pht = this.getTranslations();
       var cursor = this._cursorItem;
 
+      var changeset;
       if (cursor) {
-        if (cursor.type == 'file') {
+        changeset = cursor.changeset;
-          var changeset = cursor.changeset;
-          var editor_uri = changeset.getEditorURI();
-
-          if (editor_uri === null) {
-            this._warnUser(pht('No external editor is configured.'));
-            return;
-          }
-
-          JX.$U(editor_uri).go();
-
-          return;
-        }
       }
 
-      this._warnUser(pht('You must select a file to edit.'));
+      if (!changeset) {
+        changeset = this._getVisibleChangeset();
+      }
+
+      if (!changeset) {
+        this._warnUser(pht('You must select a file to edit.'));
+        return;
+      }
+
+      var editor_uri = changeset.getEditorURI();
+
+      if (editor_uri === null) {
+        this._warnUser(pht('No external editor is configured.'));
+        return;
+      }
+
+      JX.$U(editor_uri).go();
     },
 
     _onkeycollapse: function() {