fixup! Get rid of Products.CMFDefault.{File.File,Portal.CMFSite}

See commit 12e4cc8b.

File._setFile does not support that 'data' is a bytes object:
it crashes if there are already data stored on the object.
test_PUT_on_web_page (erp5_dms:testWebDavSupport) is changed to cover
this case and the caller of File._edit is fixed to make that 'file'
is always a file-like object.

File._setFile is also optimized to avoid reading data for nothing
if the document has no data.

bt5/erp5_dms/TestTemplateItem/portal_components/test.erp5.testWebDavSupport.py

@@ -186,6 +186,8 @@ class TestWebDavSupport(ERP5TypeTestCase):
     """
     iso_text_content = text_content.decode('utf-8').encode('iso-8859-1')
     path = web_page_module.getPath()
+    for _ in xrange(2): # Run twice to check the code that compares
+                        # old & new data when setting file attribute.
       response = self.publish('%s/%s' % (path, filename),
                               request_method='PUT',
                               stdin=StringIO(iso_text_content),

product/ERP5/bootstrap/erp5_core/DocumentTemplateItem/portal_components/document.erp5.File.py

@@ -36,6 +36,7 @@ from erp5.component.document.Document import ConversionError
 from Products.ERP5Type.Base import Base, removeIContentishInterface
 from OFS.Image import File as OFS_File
 from Products.ERP5Type.Utils import deprecated
+from cStringIO import StringIO
 
 def _unpackData(data):
   """
@@ -146,9 +147,12 @@ class File(Document, OFS_File):
   def _setFile(self, data, precondition=None):
     if data is None:
       return
-    if str(data.read()) == (self.hasData() and str(self.getData())):
+    if self.hasData():
+      if str(data.read()) == str(self.getData()):
         # Same data as previous, no need to change its content
         return
+    else:
+      data.seek(0, 2)
 
     if data.tell():
       data.seek(0)

product/ERP5/bootstrap/erp5_core/ModuleComponentTemplateItem/portal_components/module.erp5.WebDAVSupport.py

@@ -23,6 +23,7 @@ from Products.ERP5Type.Globals import InitializeClass
 from Products.ERP5Type import Permissions
 from Products.CMFCore.PortalContent import ResourceLockedError
 from zExceptions import Forbidden
+from cStringIO import StringIO
 
 security = ModuleSecurityInfo(__name__)
 
@@ -76,7 +77,7 @@ class TextContent:
       headers = self.parseHeadersFromText(body)
       content_type = REQUEST.get_header('Content-Type', '')
       headers.setdefault('content_type', content_type)
-      headers['file'] = body
+      headers['file'] = StringIO(body)
       self._edit(**headers)
     except ResourceLockedError:
       transaction.abort()