internal/lsp/cache: don't close around actionHandle or snapshot
internal/lsp/cache: don't close around actionHandle or snapshot

This change stops the memory leak from happening. It does not stop the
large number of allocations done by analysis, however, so these still
need to be prevented through correct cancellation.

Change-Id: I1cf7fbf6f85ed413af1f2ea55f91862a6d7f2db7
Reviewed-on: https://go-review.googlesource.com/c/tools/+/204558
Run-TryBot: Rebecca Stambler <d7cf11e5f299d88ea8348366a9fc4f7c335c3afa@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Ian Cottrell <52376736e5e84615ec49f9c1843b8acc178b1d8d@google.com>

golang/tools,golang/tools,golang/tools,golang/tools,golang/tools