bug#30490: 26.0; Elisp manual: indexing performance analysis

[Drew Adams]

In the Elisp manual, `i perform TAB' shows `performance analysis'.
Following that takes you to node `Coverage Testing' in the Edebug
section.  That's hardly what I'd call a topic about performance
analysis, but I didn't study it in detail.

The real bug here is that there is nothing else indexed under the
term "performance".  (Perhaps some similar word is used, but
"performance" is what came to my mind to look for.)

`i profil TAB' shows `profiling', which takes you to node `Profiling'.
Isn't that about "performance analysis"?  Shouldn't it, rather than, or
in addition to, `Coverage Testing' be indexed for "performance"?

In GNU Emacs 26.0.91 (build 1, x86_64-w64-mingw32)
 of 2018-01-22
Repository revision: 752fba992b793a74d202c9cfc3e1a92fd458e748
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --without-dbus --host=x86_64-w64-mingw32
 --without-compress-install 'CFLAGS=-O2 -static -g3''