media: Set PROTECTED_VIDEO meta data in CdmAdapter

If the current video stream is encrypted, set PROTECTED_VIDEO in the
decoded video frame.

Notes:
- clear leads in an encrypted video stream also have PROTECTED_VIDEO set
- For clear stream, even though we are using the CDM to decode it,
  PROTECTED_VIDEO will NOT be set

Bug: 849464
Change-Id: Iae3257aaa122af8073f815278d8b65b55946f3f3
Reviewed-on: https://chromium-review.googlesource.com/c/1337486
Commit-Queue: Xiaohan Wang <xhwang@chromium.org>
Reviewed-by: John Rummell <jrummell@chromium.org>
Reviewed-by: Maggie Chen <magchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#609851}

media/cdm/cdm_adapter.cc

@@ -528,6 +528,7 @@ void CdmAdapter::InitializeVideoDecoder(const VideoDecoderConfig& config,
   }
 
   pixel_aspect_ratio_ = config.GetPixelAspectRatio();
+  is_video_encrypted_ = config.is_encrypted();
 
   if (status == cdm::kDeferredInitialization) {
     DVLOG(1) << "Deferred initialization in " << __func__;
@@ -608,6 +609,11 @@ void CdmAdapter::DecryptAndDecodeVideo(scoped_refptr<DecoderBuffer> encrypted,
     return;
   }
 
+  if (is_video_encrypted_) {
+    decoded_frame->metadata()->SetBoolean(VideoFrameMetadata::PROTECTED_VIDEO,
+                                          true);
+  }
+
   video_decode_cb.Run(Decryptor::kSuccess, decoded_frame);
 }
 

media/cdm/cdm_adapter.h

@@ -252,6 +252,9 @@ class MEDIA_EXPORT CdmAdapter : public ContentDecryptionModule,
   // Keep track of aspect ratio from the latest configuration.
   double pixel_aspect_ratio_ = 0.0;
 
+  // Whether the current video config is encrypted.
+  bool is_video_encrypted_ = false;
+
   // Tracks whether an output protection query and a positive query result (no
   // unprotected external link) have been reported to UMA.
   bool uma_for_output_protection_query_reported_ = false;