This change correctly invalidates the cache when we
have to go from a trimmed to untrimmed AST.
The "ignoreFuncBodies" behavior is still disabled due to a racy test.
Updates golang/go#30309
Change-Id: I6b89d1d2140d77517616cb3956721a157c25ab71
Reviewed-on: https://go-review.googlesource.com/c/tools/+/180857
Run-TryBot: Rebecca Stambler <rstambler@golang.org>
Reviewed-by: Ian Cottrell <iancottrell@google.com>