Restore dexteritytextindexer support

plone/app/blocks/configure.zcml

@@ -211,4 +211,9 @@
              zope.lifecycleevent.interfaces.IObjectModifiedEvent"
         handler=".subscribers.onLayoutEdited" />
 
+    <adapter
+        factory=".indexing.LayoutFieldConverter"
+        zcml:condition="installed collective.dexteritytextindexer"
+        />
+
 </configure>

plone/app/blocks/indexing.py

@@ -1,10 +1,26 @@
+# -*- coding: utf-8 -*-
 from Products.CMFPlone.utils import safe_unicode
 from lxml.html import fromstring
 from lxml.html import tostring
 from plone.app.blocks.layoutbehavior import ILayoutAware
+from plone.dexterity.interfaces import IDexterityContent
 from plone.indexer.decorator import indexer
 from plone.tiles.data import ANNOTATIONS_KEY_PREFIX
+from z3c.form.interfaces import IWidget
 from zope.annotation.interfaces import IAnnotations
+from zope.component import adapter
+from zope.interface import implementer
+import pkg_resources
+
+try:
+    pkg_resources.get_distribution('collective.dexteritytextindexer')
+except pkg_resources.DistributionNotFound:
+    HAS_DEXTERITYTEXTINDEXER = False
+else:
+    from collective.dexteritytextindexer.converters import DefaultDexterityTextIndexFieldConverter  # noqa
+    from collective.dexteritytextindexer.interfaces import IDexterityTextIndexFieldConverter  # noqa
+    from collective.dexteritytextindexer.utils import searchable
+    HAS_DEXTERITYTEXTINDEXER = True
 
 try:
     from plone.app.contenttypes import indexers
@@ -52,3 +68,15 @@ def LayoutSearchableText(obj):
             text.append(tostring(el))
 
     return concat(*text)
+
+
+if HAS_DEXTERITYTEXTINDEXER:
+
+    searchable(ILayoutAware, 'content')
+
+    @implementer(IDexterityTextIndexFieldConverter)
+    @adapter(IDexterityContent, ILayoutAware, IWidget)
+    class LayoutFieldConverter(DefaultDexterityTextIndexFieldConverter):
+
+        def convert(self):
+            return LayoutSearchableText(self.context)