Reland "APM: rename `AnalogGainStatsReporter` to `InputVolumeStatsReporter`"

This reverts commit 6a18f06bd09fdeaad6e6e00d098fc50ab946ed40.

Reason for revert: reverted by mistake

Original change's description:
> Revert "APM: rename `AnalogGainStatsReporter` to `InputVolumeStatsReporter`"
>
> This reverts commit b5319fabeeda4ffbf58f28f4ee3d5c7c3868fb3b.
>
> Reason for revert: audioproc_f crash 
>
> Original change's description:
> > APM: rename `AnalogGainStatsReporter` to `InputVolumeStatsReporter`
> >
> > Adopt the new naming convention, which replaces "analog gain" and
> > "mic level" with "input volume", in the input volume stats reporter.
> >
> > Bug: webrtc:7494
> > Change-Id: Ia24876151f51dd1dcc4e4f9db56c64d11ae3b442
> > Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/279840
> > Reviewed-by: Hanna Silen <silen@webrtc.org>
> > Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
> > Cr-Commit-Position: refs/heads/main@{#38467}
>
> Bug: webrtc:7494
> Change-Id: Ia943a57c93fc77eb8450fab17961e60774e10f02
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/280600
> Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
> Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
> Auto-Submit: Alessio Bazzica <alessiob@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#38478}

Bug: webrtc:7494
Change-Id: I204133460dc119142f87695effce45e04426519f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/280582
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Alessio Bazzica <alessiob@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38479}
diff --git a/modules/audio_processing/audio_processing_impl.h b/modules/audio_processing/audio_processing_impl.h
index 3dfa8ce..bc582b5 100644
--- a/modules/audio_processing/audio_processing_impl.h
+++ b/modules/audio_processing/audio_processing_impl.h
@@ -539,7 +539,7 @@
   RmsLevel capture_output_rms_ RTC_GUARDED_BY(mutex_capture_);
   int capture_rms_interval_counter_ RTC_GUARDED_BY(mutex_capture_) = 0;
 
-  AnalogGainStatsReporter input_volume_stats_reporter_
+  InputVolumeStatsReporter applied_input_volume_stats_reporter_
       RTC_GUARDED_BY(mutex_capture_);
 
   // Lock protection not needed.