libmso: Use reserve achor in case OfficeArtClientAnchor is missing.
* Sometimes OfficeArtClientAnchor, which provides some client specific data to obtain shape dimensions and position is missing. Each client should decide what to do in this case. For MS-DOC client, the data can be accessed based on the character position (CP) in the document. I could not reproduce the problem after re-save in MS Office 2000/2003/2007. The test files attached to Bug 275290 is a well known broken file. I left an assert to obtain test data for inline shapes with missing OfficeArtClientAnchor. BUG:275290