Reland "Avoiding overflow in cross correlation in NetEq."

The original CL is https://codereview.webrtc.org/1908623002/

An error was caused by that and this CL fix that problem and reland the CL.

BUG=

Review-Url: https://codereview.webrtc.org/1931933004
Cr-Commit-Position: refs/heads/master@{#12589}
diff --git a/webrtc/modules/audio_coding/neteq/merge.h b/webrtc/modules/audio_coding/neteq/merge.h
index a168502..95dea5a 100644
--- a/webrtc/modules/audio_coding/neteq/merge.h
+++ b/webrtc/modules/audio_coding/neteq/merge.h
@@ -69,11 +69,10 @@
   // of samples that were taken from the |sync_buffer_|.
   size_t GetExpandedSignal(size_t* old_length, size_t* expand_period);
 
-  // Analyzes |input| and |expanded_signal| to find maximum values. Returns
-  // a muting factor (Q14) to be used on the new data.
+  // Analyzes |input| and |expanded_signal| and returns muting factor (Q14) to
+  // be used on the new data.
   int16_t SignalScaling(const int16_t* input, size_t input_length,
-                        const int16_t* expanded_signal,
-                        int16_t* expanded_max, int16_t* input_max) const;
+                        const int16_t* expanded_signal) const;
 
   // Downsamples |input| (|input_length| samples) and |expanded_signal| to
   // 4 kHz sample rate. The downsampled signals are written to
@@ -84,8 +83,7 @@
   // Calculates cross-correlation between |input_downsampled_| and
   // |expanded_downsampled_|, and finds the correlation maximum. The maximizing
   // lag is returned.
-  size_t CorrelateAndPeakSearch(int16_t expanded_max, int16_t input_max,
-                                size_t start_position, size_t input_length,
+  size_t CorrelateAndPeakSearch(size_t start_position, size_t input_length,
                                 size_t expand_period) const;
 
   const int fs_mult_;  // fs_hz_ / 8000.