Update to api-generator 22.9.4.

The new API generator uses ASM 5.0.4 instead of 4.0, which makes
it capable of handling class files format 52. It also drops the
dependency on the SDK common jar and only depends on Guava (and
ASM), using the offline Maven repository directly.

Change-Id: I2978d514fe7653465200612943593e10662327c9
1 file changed