[Fuchsia] Move audio stream decryptor creation to FuchsiaCdm

Previously audio and video decryptor creation logic was not consistent:
audio stream decryptor was created in FuchsiaClearStreamDecryptor::Create(),
while video stream decryptor is allocated in FuchsiaCdm. This CL removes
Create() from FuchsiaClearStreamDecryptor and adds

FuchsiaCdm: :CreateAudioDecryptor().
Change-Id: I17b4ad0d9e8b0949de9951ec2534c15f678d2e90
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2531053
Auto-Submit: Sergey Ulanov <sergeyu@chromium.org>
Commit-Queue: David Dorwin <ddorwin@chromium.org>
Reviewed-by: David Dorwin <ddorwin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#826168}

media/fuchsia/cdm/fuchsia_cdm.cc

@@ -24,6 +24,10 @@ namespace media {
 
 namespace {
 
+// Audio packets are normally smaller than 128kB (more than enough for 2 seconds
+// at 320kb/s).
+const size_t kAudioStreamBufferSize = 128 * 1024;
+
 std::string GetInitDataTypeName(EmeInitDataType type) {
   switch (type) {
     case EmeInitDataType::WEBM:
@@ -245,7 +249,7 @@ FuchsiaCdm::FuchsiaCdm(fuchsia::media::drm::ContentDecryptionModulePtr cdm,
     : cdm_(std::move(cdm)),
       ready_cb_(std::move(ready_cb)),
       session_callbacks_(std::move(callbacks)),
-      decryptor_(cdm_.get()) {
+      decryptor_(this) {
   DCHECK(cdm_);
   cdm_.events().OnProvisioned =
       fit::bind_member(this, &FuchsiaCdm::OnProvisioned);
@@ -292,6 +296,18 @@ std::unique_ptr<FuchsiaSecureStreamDecryptor> FuchsiaCdm::CreateVideoDecryptor(
   return decryptor;
 }
 
+std::unique_ptr<FuchsiaClearStreamDecryptor>
+FuchsiaCdm::CreateAudioDecryptor() {
+  fuchsia::media::drm::DecryptorParams params;
+  params.set_require_secure_mode(false);
+  params.mutable_input_details()->set_format_details_version_ordinal(0);
+  fuchsia::media::StreamProcessorPtr stream_processor;
+  cdm_->CreateDecryptor(std::move(params), stream_processor.NewRequest());
+
+  return std::make_unique<FuchsiaClearStreamDecryptor>(
+      std::move(stream_processor), kAudioStreamBufferSize);
+}
+
 void FuchsiaCdm::SetServerCertificate(
     const std::vector<uint8_t>& certificate,
     std::unique_ptr<SimpleCdmPromise> promise) {

media/fuchsia/cdm/fuchsia_cdm.h

@@ -73,6 +73,7 @@ class FuchsiaCdm : public ContentDecryptionModule,
   // FuchsiaCdmContext implementation:
   std::unique_ptr<FuchsiaSecureStreamDecryptor> CreateVideoDecryptor(
       FuchsiaSecureStreamDecryptor::Client* client) override;
+  std::unique_ptr<FuchsiaClearStreamDecryptor> CreateAudioDecryptor() override;
 
  private:
   class CdmSession;

media/fuchsia/cdm/fuchsia_cdm_context.h

@@ -17,6 +17,8 @@ class FuchsiaCdmContext {
   // Creates FuchsiaSecureStreamDecryptor instance for the CDM context.
   virtual std::unique_ptr<FuchsiaSecureStreamDecryptor> CreateVideoDecryptor(
       FuchsiaSecureStreamDecryptor::Client* client) = 0;
+  virtual std::unique_ptr<FuchsiaClearStreamDecryptor>
+  CreateAudioDecryptor() = 0;
 
  protected:
   virtual ~FuchsiaCdmContext() = default;

media/fuchsia/cdm/fuchsia_decryptor.cc

@@ -11,18 +11,14 @@
 #include "base/threading/thread_task_runner_handle.h"
 #include "media/base/decoder_buffer.h"
 #include "media/base/video_frame.h"
+#include "media/fuchsia/cdm/fuchsia_cdm_context.h"
 #include "media/fuchsia/cdm/fuchsia_stream_decryptor.h"
 
 namespace media {
 
-// Audio packets are normally smaller than 128kB (more than enough for 2 seconds
-// at 320kb/s).
-const size_t kAudioStreamBufferSize = 128 * 1024;
-
-FuchsiaDecryptor::FuchsiaDecryptor(
-    fuchsia::media::drm::ContentDecryptionModule* cdm)
-    : cdm_(cdm) {
-  DCHECK(cdm_);
+FuchsiaDecryptor::FuchsiaDecryptor(FuchsiaCdmContext* cdm_context)
+    : cdm_context_(cdm_context) {
+  DCHECK(cdm_context_);
 }
 
 FuchsiaDecryptor::~FuchsiaDecryptor() {
@@ -42,8 +38,7 @@ void FuchsiaDecryptor::Decrypt(StreamType stream_type,
 
   if (!audio_decryptor_) {
     audio_decryptor_task_runner_ = base::ThreadTaskRunnerHandle::Get();
-    audio_decryptor_ =
-        FuchsiaClearStreamDecryptor::Create(cdm_, kAudioStreamBufferSize);
+    audio_decryptor_ = cdm_context_->CreateAudioDecryptor();
   }
 
   audio_decryptor_->Decrypt(std::move(encrypted), std::move(decrypt_cb));

media/fuchsia/cdm/fuchsia_decryptor.h

@@ -14,22 +14,15 @@
 #include "media/base/decryptor.h"
 #include "media/fuchsia/cdm/fuchsia_stream_decryptor.h"
 
-namespace fuchsia {
-namespace media {
-namespace drm {
-class ContentDecryptionModule;
-}  // namespace drm
-}  // namespace media
-}  // namespace fuchsia
-
 namespace media {
 
+class FuchsiaCdmContext;
 class FuchsiaClearStreamDecryptor;
 
 class FuchsiaDecryptor : public Decryptor {
  public:
   // Caller should make sure |cdm| lives longer than this class.
-  explicit FuchsiaDecryptor(fuchsia::media::drm::ContentDecryptionModule* cdm);
+  explicit FuchsiaDecryptor(FuchsiaCdmContext* cdm_context);
   ~FuchsiaDecryptor() override;
 
   // media::Decryptor implementation:
@@ -50,7 +43,7 @@ class FuchsiaDecryptor : public Decryptor {
   bool CanAlwaysDecrypt() override;
 
  private:
-  fuchsia::media::drm::ContentDecryptionModule* const cdm_;
+  FuchsiaCdmContext* const cdm_context_;
 
   std::unique_ptr<FuchsiaClearStreamDecryptor> audio_decryptor_;
 

media/fuchsia/cdm/fuchsia_stream_decryptor.cc

@@ -216,22 +216,6 @@ void FuchsiaStreamDecryptorBase::ProcessEndOfStream() {
   processor_.ProcessEos();
 }
 
-std::unique_ptr<FuchsiaClearStreamDecryptor>
-FuchsiaClearStreamDecryptor::Create(
-    fuchsia::media::drm::ContentDecryptionModule* cdm,
-    size_t min_buffer_size) {
-  DCHECK(cdm);
-
-  fuchsia::media::drm::DecryptorParams params;
-  params.set_require_secure_mode(false);
-  params.mutable_input_details()->set_format_details_version_ordinal(0);
-  fuchsia::media::StreamProcessorPtr stream_processor;
-  cdm->CreateDecryptor(std::move(params), stream_processor.NewRequest());
-
-  return std::make_unique<FuchsiaClearStreamDecryptor>(
-      std::move(stream_processor), min_buffer_size);
-}
-
 FuchsiaClearStreamDecryptor::FuchsiaClearStreamDecryptor(
     fuchsia::media::StreamProcessorPtr processor,
     size_t min_buffer_size)