Add alaw codec for .wav files.

content/browser/media/media_browsertest.cc

Index: content/browser/media/media_browsertest.cc
===================================================================
--- content/browser/media/media_browsertest.cc	(revision 232774)
+++ content/browser/media/media_browsertest.cc	(working copy)
@@ -168,16 +168,20 @@
   PlayAudio("bear_gsm_ms.wav", GetParam());
 }
 
-IN_PROC_BROWSER_TEST_P(MediaTest, VideoBearWavMulaw) {
-  PlayAudio("bear_mulaw.wav", GetParam());
-}
-
 IN_PROC_BROWSER_TEST_P(MediaTest, VideoBearFlac) {
   PlayAudio("bear.flac", GetParam());
 }
 #endif
 #endif
 
+IN_PROC_BROWSER_TEST_P(MediaTest, VideoBearWavAlaw) {
+  PlayAudio("bear_alaw.wav", GetParam());
+}
+
+IN_PROC_BROWSER_TEST_P(MediaTest, VideoBearWavMulaw) {
+  PlayAudio("bear_mulaw.wav", GetParam());
+}
+
 IN_PROC_BROWSER_TEST_P(MediaTest, VideoBearWavPcm) {
   PlayAudio("bear_pcm.wav", GetParam());
 }