Use an inline dialog element for inline comments in Differential

Summary:
The current approach of using a modal overlay dialog to create/edit inline
comments is pretty silly. Use an inline textarea instead.

This element isn't perfect and we have some mild modalness issues, but I think
it's better than the silly thing we've got going on right now. We can keep
poking it as people break it.

Test Plan:
  - Created comments; submitted and undid them in empty and nonempty states.
Used undo for nonempty states + cancel.
  - Edited comments; saved and canceled them. Used undo for changed state.
  - Replied to comments; yada yada as above.
  - Deleted comments.
  - Did various modal trickery where I clicked "Reply" on something else with a
dialog already up, this very mildly glitches but I think it's not a big issue.

Reviewers: vrana, btrahan, Makinde, nh

Reviewed By: vrana

CC: aran, epriestley

Maniphest Tasks: T431

Differential Revision: https://secure.phabricator.com/D1716

webroot/rsrc/js/application/differential/behavior-edit-inline-comments.js

@@ -50,6 +50,7 @@ JX.behavior('differential-edit-inline-comments', function(config) {
     selecting = false;
     editor = false;
     hideReticle();
+    set_link_state(false);
   });
 
   function isOnRight(node) {
@@ -69,6 +70,10 @@ JX.behavior('differential-edit-inline-comments', function(config) {
     }
   }
 
+  var set_link_state = function(active) {
+    JX.DOM.alterClass(JX.$(config.stage), 'inline-editor-active', active);
+  };
+
   JX.Stratcom.listen(
     'mousedown',
     ['differential-changeset', 'tag:th'],
@@ -148,6 +153,8 @@ JX.behavior('differential-edit-inline-comments', function(config) {
         .setTable(insert.parentNode)
         .start();
 
+      set_link_state(true);
+
       e.kill();
     });
 
@@ -183,9 +190,14 @@ JX.behavior('differential-edit-inline-comments', function(config) {
     });
 
   var action_handler = function(op, e) {
+    e.kill();
+
+    if (editor) {
+      return;
+    }
+
     var node = e.getNode('differential-inline-comment');
     handle_inline_action(node, op);
-    e.kill();
   }
 
   var handle_inline_action = function(node, op) {
@@ -208,6 +220,8 @@ JX.behavior('differential-edit-inline-comments', function(config) {
       .setRow(row)
       .setTable(row.parentNode)
       .start();
+
+    set_link_state(true);
   }
 
   for (var op in {'edit' : 1, 'delete' : 1, 'reply' : 1}) {