Revert "doc/go1.17: mention block profile bias fix"

This reverts CL 324471 (commit 689f4c7).

Reason for revert: break ~all builders. And it is not a doc-only change.

Change-Id: Iadbdda34d2ca476a9f5e6c2d3a28592ed7ccb067
Reviewed-on: https://go-review.googlesource.com/c/go/+/326170
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>

doc/go1.17.html

@@ -737,16 +737,6 @@ <h3 id="minor_library_changes">Minor changes to the library</h3>
  </dd>
 </dl><!-- runtime/metrics -->
 
-
-<dl id="runtime/pprof"><dt><a href="/pkg/runtime/pprof">runtime/pprof</a></dt>
- <dd>
- <p><!-- CL 299991 -->
- Block profiles are no longer biased to favor infrequent long events over
- frequent short events.
- </p>
- </dd>
-</dl><!-- runtime/pprof -->
-
 <dl id="strconv"><dt><a href="/pkg/strconv/">strconv</a></dt>
  <dd>
  <p><!-- CL 170079 -->

src/runtime/pprof/pprof_test.go

@@ -106,28 +106,6 @@ func TestCPUProfileMultithreaded(t *testing.T) {
  })
 }
 
-func TestCPUProfileThreadBias(t *testing.T) {
- cpuHogA := func(dur time.Duration) {
- cpuHogger(cpuHog1, &salt2, dur)
- }
-
- defer runtime.GOMAXPROCS(runtime.GOMAXPROCS(2))
- prof := testCPUProfile(t, stackContains, []string{"runtime/pprof.cpuHog1", "runtime/pprof.cpuHog2"}, avoidFunctions(), func(dur time.Duration) {
- //c := make(chan int)
- //go func() {
- //cpuHogger(cpuHog1, &salt1, dur)
- //c <- 1
- //}()
- cpuHogA(dur)
- //<-c
- })
- fmt.Printf("%#v\n", prof)
-}
-
-func cpuHogA(dur time.Duration) {
- cpuHogger(cpuHog1, &salt2, dur)
-}
-
 // containsInlinedCall reports whether the function body for the function f is
 // known to contain an inlined function call within the first maxBytes bytes.
 func containsInlinedCall(f interface{}, maxBytes int) bool {