Update a ton of audio code to use size_t more correctly and in general reduce

webrtc/common_audio/signal_processing/filter_ar.c

 /*
  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 
 /*
  * This file contains the function WebRtcSpl_FilterAR().
  * The description header can be found in signal_processing_library.h
  *
  */
 
 #include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
 
-int WebRtcSpl_FilterAR(const int16_t* a,
-                       int a_length,
-                       const int16_t* x,
-                       int x_length,
-                       int16_t* state,
-                       int state_length,
-                       int16_t* state_low,
-                       int state_low_length,
-                       int16_t* filtered,
-                       int16_t* filtered_low,
-                       int filtered_low_length)
+size_t WebRtcSpl_FilterAR(const int16_t* a,
+                          size_t a_length,
+                          const int16_t* x,
+                          size_t x_length,
+                          int16_t* state,
+                          size_t state_length,
+                          int16_t* state_low,
+                          size_t state_low_length,
+                          int16_t* filtered,
+                          int16_t* filtered_low,
+                          size_t filtered_low_length)
 {
     int32_t o;
     int32_t oLOW;
-    int i, j, stop;
+    size_t i, j, stop;
     const int16_t* x_ptr = &x[0];
     int16_t* filteredFINAL_ptr = filtered;
     int16_t* filteredFINAL_LOW_ptr = filtered_low;
 
     for (i = 0; i < x_length; i++)
     {
         // Calculate filtered[i] and filtered_low[i]
         const int16_t* a_ptr = &a[1];
         int16_t* filtered_ptr = &filtered[i - 1];
         int16_t* filtered_low_ptr = &filtered_low[i - 1];
@@ skipping 35 matching lines @@
         }
         for (i = 0; i < x_length; i++)
         {
             state[state_length - x_length + i] = filtered[i];
             state[state_length - x_length + i] = filtered_low[i];
         }
     }
 
     return x_length;
 }