Initialize libyuv CPU features in a thread safe manner.

media/base/media.cc

Index: media/base/media.cc
diff --git a/media/base/media.cc b/media/base/media.cc
index 8ad82ee2babf74eaeb363a93e613a83fce35103b..77720b44a0a24255d10808980b8cbe6e1ebd667c 100644
--- a/media/base/media.cc
+++ b/media/base/media.cc
@@ -9,6 +9,7 @@
 #include "base/metrics/field_trial.h"
 #include "base/trace_event/trace_event.h"
 #include "media/base/media_switches.h"
+#include "third_party/libyuv/include/libyuv.h"
 
 #if defined(OS_ANDROID)
 #include "base/android/build_info.h"
@@ -28,6 +29,8 @@ class MediaInitializer {
     TRACE_EVENT_WARMUP_CATEGORY("audio");
     TRACE_EVENT_WARMUP_CATEGORY("media");
 
+    libyuv::InitCpuFlags();
+
 #if !defined(MEDIA_DISABLE_FFMPEG)
     // Initialize CPU flags outside of the sandbox as this may query /proc for
     // details on the current CPU for NEON, VFP, etc optimizations.