Remove name from InputMonitor

InputMonitor already contains an inputchannel. And inputchannel has a
name. Using the latest codegen tool, toString would already properly
print name because InputChannel has toString. So we don't need to
duplicate this field in InputMonitor.

Bug: 142581626
Test: presubmit
Change-Id: I2915cdc9928ab50991539593e584173e2231c16f