MediaMetrics: Fix clang-tidy narrowing warning

Test: compiles
Bug: 182410845
Change-Id: I49d4362cccd49c5afc983ad03736607164d0195e
diff --git a/services/mediametrics/AudioAnalytics.cpp b/services/mediametrics/AudioAnalytics.cpp
index 45c9f56..2d0d2f4 100644
--- a/services/mediametrics/AudioAnalytics.cpp
+++ b/services/mediametrics/AudioAnalytics.cpp
@@ -967,10 +967,10 @@
         if (channelMask != 0) {
             switch (direction) {
                 case 1: // Output, keep sync with AudioTypes#getAAudioDirection()
-                    channelCount = audio_channel_count_from_out_mask(channelMask);
+                    channelCount = (int32_t)audio_channel_count_from_out_mask(channelMask);
                     break;
                 case 2: // Input, keep sync with AudioTypes#getAAudioDirection()
-                    channelCount = audio_channel_count_from_in_mask(channelMask);
+                    channelCount = (int32_t)audio_channel_count_from_in_mask(channelMask);
                     break;
                 default:
                     ALOGW("Invalid direction %d", direction);
diff --git a/services/mediametrics/statsd_drm.cpp b/services/mediametrics/statsd_drm.cpp
index 287fb8d..e06a605 100644
--- a/services/mediametrics/statsd_drm.cpp
+++ b/services/mediametrics/statsd_drm.cpp
@@ -171,7 +171,7 @@
     std::vector<uint8_t> buf(str.length() / 4 * 3, 0);
     size_t size = buf.size();
     if (decodeBase64(buf.data(), &size, str.c_str()) && size <= buf.size()) {
-        buf.erase(buf.begin() + size, buf.end());
+        buf.erase(buf.begin() + (ptrdiff_t)size, buf.end());
         return buf;
     }
     return {};