Fix rendering identical blocks after re-parsing HTML

Fixes #662. Regression introduced very subtly (by me) in #355.

src/trix/views/object_view.coffee

@@ -12,6 +12,7 @@ class Trix.ObjectView extends Trix.BasicObject
 
   invalidate: ->
     @nodes = null
+    @childViews = []
     @parentView?.invalidate()
 
   invalidateViewForObject: (object) ->
@@ -36,8 +37,7 @@ class Trix.ObjectView extends Trix.BasicObject
   recordChildView: (view) ->
     view.parentView = this
     view.rootView = @rootView
-    unless view in @childViews
-      @childViews.push(view)
+    @childViews.push(view)
     view
 
   getAllChildViews: ->

test/src/system/html_reparsing_test.coffee

@@ -0,0 +1,24 @@
+{assert, test, testGroup} = Trix.TestHelpers
+
+testGroup "HTML Reparsing", template: "editor_empty", ->
+  test "mutation resulting in identical blocks", (expectDocument) ->
+    element = getEditorElement()
+    element.editor.loadHTML("<ul><li>a</li><li>b</li></ul>")
+    requestAnimationFrame ->
+      element.querySelector("li").textContent = "b"
+      requestAnimationFrame ->
+        assert.blockAttributes([0, 1], ["bulletList", "bullet"])
+        assert.blockAttributes([2, 3], ["bulletList", "bullet"])
+        assert.equal(element.value, "<ul><li>b</li><li>b</li></ul>")
+        expectDocument("b\nb\n")
+
+  test "mutation resulting in identical pieces", (expectDocument) ->
+    element = getEditorElement()
+    element.editor.loadHTML("<div><strong>a</strong> <strong>b</strong></div>")
+    requestAnimationFrame ->
+      element.querySelector("strong").textContent = "b"
+      requestAnimationFrame ->
+        assert.textAttributes([0, 1], bold: true)
+        assert.textAttributes([2, 3], bold: true)
+        assert.equal(element.value, "<div><strong>b</strong> <strong>b</strong></div>")
+        expectDocument("b b\n")