XWiki.renameDocument fails silently on failed object copy

When an object on a page that is being renamed fails to be saved in its new page(at least in the case where the object contains a field that is not part of the current schema for its class) the renameDocument call does not indicate an error, nor does it abort or roll back the document rename transaction. As a result, the cache is not cleared of the changed document, so that within the same session, before a cache flush, all appears well. In reality, the document is renamed, but its objects are no longer attached to it.

This was the original presenting symptom that led to discovery of bug XWIKI-341.

Though I have not checked it, I believe the same scenario is true for copyDocument.