Enable ply an importable module. Bug: 153941871 Test: build manually Change-Id: Iafb1c669c16b20eec288bad6d2ea530f0d3ab2a8 Merged-In: Iafb1c669c16b20eec288bad6d2ea530f0d3ab2a8 Merged-In: Ic48b01d0365bc8443986533746e149b7aa2c8cfc