base/conversion: setContentType before converting to base format

some conversion (TextDocument) depend on the content type, so it's
necessary to first update the content type before trying to convert to
base format

bt5/erp5_base/WorkflowTemplateItem/portal_workflow/document_conversion_interaction_workflow/interaction_Document_base_convertable.xml

@@ -10,8 +10,9 @@
             <key> <string>categories</string> </key>
             <value>
               <tuple>
-                <string>after_script/portal_workflow/document_conversion_interaction_workflow/script_Document_convertToBaseFormat</string>
+                <string>after_script/portal_workflow/document_conversion_interaction_workflow/script_Document_guessMimeType</string>
                 <string>after_script/portal_workflow/document_conversion_interaction_workflow/script_Document_upload</string>
+                <string>after_script/portal_workflow/document_conversion_interaction_workflow/script_Document_convertToBaseFormat</string>
               </tuple>
             </value>
         </item>

bt5/erp5_base/WorkflowTemplateItem/portal_workflow/document_conversion_interaction_workflow/interaction_Document_file.xml

-<?xml version="1.0"?>
-<ZopeData>
-  <record id="1" aka="AAAAAAAAAAE=">
-    <pickle>
-      <global name="Interaction Workflow Interaction" module="erp5.portal_type"/>
-    </pickle>
-    <pickle>
-      <dictionary>
-        <item>
-            <key> <string>categories</string> </key>
-            <value>
-              <tuple>
-                <string>after_script/portal_workflow/document_conversion_interaction_workflow/script_Document_guessMimeType</string>
-              </tuple>
-            </value>
-        </item>
-        <item>
-            <key> <string>description</string> </key>
-            <value>
-              <none/>
-            </value>
-        </item>
-        <item>
-            <key> <string>guard_expression</string> </key>
-            <value> <string>here/hasFilename</string> </value>
-        </item>
-        <item>
-            <key> <string>guard_group</string> </key>
-            <value>
-              <tuple/>
-            </value>
-        </item>
-        <item>
-            <key> <string>guard_permission</string> </key>
-            <value>
-              <tuple/>
-            </value>
-        </item>
-        <item>
-            <key> <string>guard_role</string> </key>
-            <value>
-              <tuple/>
-            </value>
-        </item>
-        <item>
-            <key> <string>id</string> </key>
-            <value> <string>interaction_Document_file</string> </value>
-        </item>
-        <item>
-            <key> <string>portal_type</string> </key>
-            <value> <string>Interaction Workflow Interaction</string> </value>
-        </item>
-        <item>
-            <key> <string>portal_type_filter</string> </key>
-            <value>
-              <tuple/>
-            </value>
-        </item>
-        <item>
-            <key> <string>portal_type_group_filter</string> </key>
-            <value>
-              <tuple/>
-            </value>
-        </item>
-        <item>
-            <key> <string>temporary_document_disallowed</string> </key>
-            <value> <int>0</int> </value>
-        </item>
-        <item>
-            <key> <string>trigger_method_id</string> </key>
-            <value>
-              <tuple>
-                <string>_setFile</string>
-                <string>_setData</string>
-              </tuple>
-            </value>
-        </item>
-        <item>
-            <key> <string>trigger_once_per_transaction</string> </key>
-            <value> <int>0</int> </value>
-        </item>
-        <item>
-            <key> <string>trigger_type</string> </key>
-            <value> <int>2</int> </value>
-        </item>
-      </dictionary>
-    </pickle>
-  </record>
-</ZopeData>

bt5/erp5_base/WorkflowTemplateItem/portal_workflow/document_conversion_interaction_workflow/script_Document_guessMimeType.py

@@ -2,7 +2,7 @@ document = state_change['object']
 portal = document.getPortalObject()
 
 filename = document.getFilename()
-content_type = portal.mimetypes_registry.lookupExtension(filename)
-
-if content_type is not None:
-  document.setContentType(str(content_type))
+if filename:
+  content_type = portal.mimetypes_registry.lookupExtension(filename)
+  if content_type is not None:
+    document.setContentType(str(content_type))