Remove deprecation warning for INameFromTitle as it breaks some use c…

…ases.

See plone/plone.app.dexterity#379 (comment)

news/3858.internal

@@ -0,0 +1,5 @@
+Mark ``INameFromTitle`` deprecated, in this distribution, as it has been moved to ``plone.base``.
+It will be removed in Plone 7.0.
+We do not show a deprecation warning, because doing so would break content types with this interface name in the behaviors list.
+Recommended is to use ``plone.namefromtitle`` as behavior name, then it works in all supported Plone versions.
+[gforcada]

plone/app/content/interfaces.py

@@ -1,14 +1,30 @@
+from plone.base.interfaces import INameFromTitle as FutureINameFromTitle
 from zope.interface import Attribute
 from zope.interface import Interface
 
-import zope.deferredimport
 
+class INameFromTitle(FutureINameFromTitle):
+    """An object that supports getting its name (id) from its title.
 
-zope.deferredimport.deprecated(
-    "It has been moved to plone.base.interfaces. "
-    "This alias will be removed in Plone 7.0",
-    INameFromTitle="plone.base.interfaces:INameFromTitle",
-)
+    This interface has been moved to plone.base.interfaces.
+    This alias will be removed in Plone 7.0.
+    We tried deprecating it like this:
+
+        zope.deferredimport.deprecated(
+            INameFromTitle="plone.base.interfaces:INameFromTitle",
+        )
+
+    Unfortunately this does not completely work: if your site has a content
+    type with behavior `plone.app.content.interfaces.INameFromTitle` this would
+    no longer work because the behavior is not found.
+    If you use `plone.namefromtitle` then it works.
+
+    So as long as we want to support the old spelling, we must keep the
+    interface here, and also use this interface as the `provides` in the
+    definition of the behavior in `plone.app.dexterity`.
+
+    See https://github.com/plone/plone.app.dexterity/pull/379
+    """
 
 
 class IReindexOnModify(Interface):