Encrypted media: avoid resetting video state on audio deinit

content/renderer/pepper/content_decryptor_delegate.cc

Index: content/renderer/pepper/content_decryptor_delegate.cc
diff --git a/content/renderer/pepper/content_decryptor_delegate.cc b/content/renderer/pepper/content_decryptor_delegate.cc
index 53ff21b0082a75d7caed1096c201290220aa10c8..02dee8a6e20bd792877a90fbfc24762725b7e80f 100644
--- a/content/renderer/pepper/content_decryptor_delegate.cc
+++ b/content/renderer/pepper/content_decryptor_delegate.cc
@@ -471,7 +471,8 @@ bool ContentDecryptorDelegate::DeinitializeDecoder(
     Decryptor::StreamType stream_type) {
   CancelDecode(stream_type);
 
-  natural_size_ = gfx::Size();
+  if (stream_type == Decryptor::kVideo)
+    natural_size_ = gfx::Size();
 
   // TODO(tomfinegan): Add decoder deinitialize request tracking, and get
   // stream type from media stack.