Fix Chromium clang plugin warnings

webrtc/modules/audio_coding/test/PCMFile.cc

Index: webrtc/modules/audio_coding/test/PCMFile.cc
diff --git a/webrtc/modules/audio_coding/test/PCMFile.cc b/webrtc/modules/audio_coding/test/PCMFile.cc
index 9289d73baa7e044b14fe3e8a03c7f51b8e9e04db..b4acf350055def237584cccd45153536b2114ebe 100644
--- a/webrtc/modules/audio_coding/test/PCMFile.cc
+++ b/webrtc/modules/audio_coding/test/PCMFile.cc
@@ -46,6 +46,12 @@ PCMFile::PCMFile(uint32_t timestamp)
   timestamp_ = timestamp;
 }
 
+PCMFile::~PCMFile() {
+  if (pcm_file_) {
+    fclose(pcm_file_);
+  }
+}
+
 int16_t PCMFile::ChooseFile(std::string* file_name, int16_t max_len,
                             uint16_t* frequency_hz) {
   char tmp_name[MAX_FILE_NAME_LENGTH_BYTE];