AssetGraph: Removed no longer used _indices property.
AssetGraph: Removed no longer used _indices property.

papandreou/assetgraph,papandreou/assetgraph,jscinoz/assetgraph,jscinoz/assetgraph,slang800/assetgraph,papandreou/assetgraph,jscinoz/assetgraph,slang800/assetgraph,assetgraph/assetgraph