winex11: Add error checks around every XF86VidMode call.

[wine] / dlls / msxml4 / msxml4.manifest

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
  <assemblyIdentity type="win32" name="Microsoft.MSXML2" version="4.1.0.0" processorArchitecture="" publicKeyToken="6bd6b9abf345378f"/>
  <file name="msxml4.dll"/>
</assembly>