"All languages" suffix not working nicely with multi-value fields

Still applies cleanly to 7.x-1.x-dev. Tested with all core field types and widgets on a clean D7.50

Pros:

• + 1: For coming even closer to the intented functionality as stated in the function's comment => "If the given element does not have a #title attribute, the function is recursively applied to child elements." The new code reads exactly in this order.
• + 1: For providing simpler code

Cons:

It is probably not wise to skip checking which FAPI elements should get the 'all languages' suffix. Letting this run without constraints could present problems with nested containers that get a '#title' property, as per the inline comment already state:

// ... "The reason for this check
// is because some elements have a #title attribute even though it is not
// rendered, e.g. field containers."

Alternative:

The current logic dictates that we should respect the FAPI definitions for elements with a #title property.
This presents the problem discussed here, that the suffix will apply to all children of a multivalue field. And this problem is actually specific to the cardinality property of a FAPI element (call me multivalue).
Maybe it would be wiser instead of doing away with the sanity checks provided by the current code, to try this instead:

elseif (isset($element['#title']) && isset($element['#cardinality']) && $element['#cardinality'] != 1) {
  // This is the case of a multi-value field
}

Supplied patch attempts to solve the reported problem with a bit less "disruptive" means.

@stefanos.petrakis:

I fully agree on your analysis and the fix looks good and works well. I'm fixing the minor nitpick below on commit, thanks!

+++ b/sites/all/modules/entity_translation/entity_translation.module
@@ -1464,6 +1464,10 @@ function _entity_translation_element_title_append(&$element, $suffix) {
+  // If this is a multi-valued field, apply the suffix to the container

Missing trailing dot :)

Committed and pushed, thanks.