Change ChunkDemuxerStream/SourceBufferStream memory limit to size_t type

media/filters/source_buffer_stream_unittest.cc

Index: media/filters/source_buffer_stream_unittest.cc
diff --git a/media/filters/source_buffer_stream_unittest.cc b/media/filters/source_buffer_stream_unittest.cc
index 8270bd9ea68fb6f71a4e630829adab0d8ba3aa18..13d98ed892bc639063cc9b125e2c6d73c5764f5c 100644
--- a/media/filters/source_buffer_stream_unittest.cc
+++ b/media/filters/source_buffer_stream_unittest.cc
@@ -38,7 +38,7 @@ class SourceBufferStreamTest : public testing::Test {
     stream_.reset(new SourceBufferStream(video_config_, log_cb(), true));
   }
 
-  void SetMemoryLimit(int buffers_of_data) {
+  void SetMemoryLimit(size_t buffers_of_data) {
     stream_->set_memory_limit(buffers_of_data * kDataSize);
   }