go/ast, go/doc, godoc: consider struct fields and interface methods when filtering ASTs
So far, only top-level names where considered when trimming ASTs
using a filter function. For instance, "godoc reflect Implements"
didn't show the "Implements" method of the type Interface because
the local method name was not considered (on the other hand, "top-
level" declared methods associated with types were considered).
With this CL, AST filter functions look also at struct fields
and interface methods.
R=rsc, r
CC=golang-dev
https://golang.org/cl/
4518050