Bug 874325 - Add lock to MediaStreamSource::readAt(). r=doublec

content/media/omx/OmxDecoder.cpp

@@ -98,6 +98,7 @@ ssize_t MediaStreamSource::readAt(off64_t offset, void *data, size_t size)
   char *ptr = static_cast<char *>(data);
   size_t todo = size;
   while (todo > 0) {
+    Mutex::Autolock autoLock(mLock);
     uint32_t bytesRead;
     if ((offset != mResource->Tell() &&
          NS_FAILED(mResource->Seek(nsISeekableStream::NS_SEEK_SET, offset))) ||

content/media/omx/OmxDecoder.h

@@ -42,6 +42,7 @@ class MediaStreamSource : public DataSource {
   typedef mozilla::MediaResource MediaResource;
   typedef mozilla::AbstractMediaDecoder AbstractMediaDecoder;
 
+  Mutex mLock;
   nsRefPtr<MediaResource> mResource;
   AbstractMediaDecoder *mDecoder;
 public: