Convert some more things to size_t.

These changes stem from requests by Andrew on https://codereview.webrtc.org/1228823002/ to eliminate some "return -1"s and change to using asserts plus returning size_ts.  I then also converted the relevant connected bits.

This also cleans up a bunch of style issues, e.g. no spaces around operators.

BUG=chromium:81439
TEST=none
R=andrew@webrtc.org, henrik.lundin@webrtc.org, niklas.enbom@webrtc.org

Review URL: https://codereview.webrtc.org/1305983003 .

Cr-Commit-Position: refs/heads/master@{#9813}
diff --git a/webrtc/modules/audio_coding/neteq/expand.cc b/webrtc/modules/audio_coding/neteq/expand.cc
index c163fee..2aa9fb0 100644
--- a/webrtc/modules/audio_coding/neteq/expand.cc
+++ b/webrtc/modules/audio_coding/neteq/expand.cc
@@ -467,8 +467,7 @@
         correlation_length, correlation_lags, correlation_scale, -1);
 
     // Find maximizing index.
-    best_index = static_cast<size_t>(
-        WebRtcSpl_MaxIndexW32(correlation_vector2, correlation_lags));
+    best_index = WebRtcSpl_MaxIndexW32(correlation_vector2, correlation_lags);
     int32_t max_correlation = correlation_vector2[best_index];
     // Compensate index with start offset.
     best_index = best_index + start_index;