media: Always provide CdmContext when selecting decoder in DecoderStream

content/renderer/media/cdm/ppapi_decryptor.cc

Index: content/renderer/media/cdm/ppapi_decryptor.cc
diff --git a/content/renderer/media/cdm/ppapi_decryptor.cc b/content/renderer/media/cdm/ppapi_decryptor.cc
index 835907cbf2e4ba4671334ea38519d387e292a637..ae9d90ad517cc06095720c5c50c7ea650225aaec 100644
--- a/content/renderer/media/cdm/ppapi_decryptor.cc
+++ b/content/renderer/media/cdm/ppapi_decryptor.cc
@@ -205,7 +205,8 @@ media::CdmContext* PpapiDecryptor::GetCdmContext() {
 }
 
 media::Decryptor* PpapiDecryptor::GetDecryptor() {
-  return this;
+  base::AutoLock auto_lock(lock_);
+  return had_fatal_plugin_error_ ? nullptr : this;
 }
 
 int PpapiDecryptor::GetCdmId() const {
@@ -436,8 +437,12 @@ void PpapiDecryptor::AttemptToResumePlayback() {
 }
 
 void PpapiDecryptor::OnFatalPluginError() {
+  DVLOG(1) << __func__;
   DCHECK(render_task_runner_->BelongsToCurrentThread());
   pepper_cdm_wrapper_.reset();
+
+  base::AutoLock auto_lock(lock_);
+  had_fatal_plugin_error_ = true;
 }
 
 ContentDecryptorDelegate* PpapiDecryptor::CdmDelegate() {