am 94364b91: surfaceflinger: don\'t check HWComposer numLayers unless one exists

Merge commit '94364b91a2894bf037b8beb027132fbb812e1434' into gingerbread-plus-aosp

* commit '94364b91a2894bf037b8beb027132fbb812e1434':
  surfaceflinger: don't check HWComposer numLayers unless one exists