Add UMA reporting to CdmPromise.

content/renderer/media/webcontentdecryptionmodulesession_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.

[ddorwin, 2014/08/08 03:35:40]

Questions for discussion:
Prefixed EME splits rejections (and even some resolves) up between Blink and
Chromium. Should we record all of them?
Are we not recording UMAs for total calls? Would total - (success + failure) be
meaningful?

[sandersd (OOO until July 31), 2014/08/08 17:22:24]

That was the original plan, but Xiaohan convinced me that UMAs are not really
the place for this kind of debugging.

Hopefully we don't need it either, since ContentDecryptorDelegate and
ProxyMediaKeys both reject all pending promises when destructed, and
AesDecryptor can't fail.

 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/media/webcontentdecryptionmodulesession_impl.h"
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/renderer/media/cdm_session_adapter.h"
 #include "media/base/cdm_promise.h"
 #include "third_party/WebKit/public/platform/WebURL.h"
 
 namespace content {
 
+const char kNewSessionUMASuffix[] = ".NewSession";

[ddorwin, 2014/08/08 03:35:40]

s/Suffix/Name/ - you can't have a prefix and suffix without a body. :)
Also, consider putting the '.' someplace common. Maybe even have a
BuildUMAName() function.

[ddorwin, 2014/08/08 03:35:40]

The actual method is createSession. It was just odd naming since we create the
WCDMS before.
Update the description too.

[sandersd (OOO until July 31), 2014/08/08 17:22:24]

Done.

[sandersd (OOO until July 31), 2014/08/08 17:22:24]

Done.

+
 // For backwards compatibility with blink not using
 // WebContentDecryptionModuleResult, reserve an index for |outstanding_results_|
 // that will not be used when adding a WebContentDecryptionModuleResult.
 // TODO(jrummell): Remove once blink always uses
 // WebContentDecryptionModuleResult.
 const uint32 kReservedIndex = 0;
 
 static blink::WebContentDecryptionModuleException ConvertException(
     media::MediaKeys::Exception exception_code) {
   switch (exception_code) {
@@ skipping 46 matching lines @@
 }
 
 void WebContentDecryptionModuleSessionImpl::setClientInterface(Client* client) {
   client_ = client;
 }
 
 blink::WebString WebContentDecryptionModuleSessionImpl::sessionId() const {
   return blink::WebString::fromUTF8(web_session_id_);
 }
 
 void WebContentDecryptionModuleSessionImpl::initializeNewSession(

[ddorwin, 2014/08/08 03:35:40]

I think this should be deleted now - it looks like an older version of the API
at l139.

[sandersd (OOO until July 31), 2014/08/08 17:22:24]

That's true, but it's still plumbed through to Blink, so I'd rather create
separate CLs.

     const blink::WebString& init_data_type,
     const uint8* init_data,
     size_t init_data_length) {
   // TODO(ddorwin): Guard against this in supported types check and remove this.
   // Chromium only supports ASCII MIME types.
   if (!base::IsStringASCII(init_data_type)) {
     NOTREACHED();
     OnSessionError(media::MediaKeys::NOT_SUPPORTED_ERROR,
                    0,
                    "The initialization data type " + init_data_type.utf8() +
                        " is not supported by the key system.");
     return;
   }
 
   std::string init_data_type_as_ascii = base::UTF16ToASCII(init_data_type);
   DLOG_IF(WARNING, init_data_type_as_ascii.find('/') != std::string::npos)
       << "init_data_type '" << init_data_type_as_ascii
       << "' may be a MIME type";
 
   scoped_ptr<media::NewSessionCdmPromise> promise(
       new media::NewSessionCdmPromise(
           base::Bind(&WebContentDecryptionModuleSessionImpl::SessionCreated,
                      weak_ptr_factory_.GetWeakPtr(),
                      kReservedIndex),
           base::Bind(&WebContentDecryptionModuleSessionImpl::OnSessionError,
-                     weak_ptr_factory_.GetWeakPtr())));
+                     weak_ptr_factory_.GetWeakPtr()),
+          adapter_->GetKeySystemUMAPrefix() + kNewSessionUMASuffix));
   adapter_->InitializeNewSession(init_data_type_as_ascii,
                                  init_data,
                                  init_data_length,
                                  media::MediaKeys::TEMPORARY_SESSION,
                                  promise.Pass());
 }
 
 void WebContentDecryptionModuleSessionImpl::update(const uint8* response,
                                                    size_t response_length) {
   DCHECK(response);
@@ skipping 40 matching lines @@
       << "init_data_type '" << init_data_type_as_ascii
       << "' may be a MIME type";
 
   scoped_ptr<media::NewSessionCdmPromise> promise(
       new media::NewSessionCdmPromise(
           base::Bind(&WebContentDecryptionModuleSessionImpl::SessionCreated,
                      weak_ptr_factory_.GetWeakPtr(),
                      result_index),
           base::Bind(&WebContentDecryptionModuleSessionImpl::SessionError,
                      weak_ptr_factory_.GetWeakPtr(),
-                     result_index)));
+                     result_index),
+          adapter_->GetKeySystemUMAPrefix() + kNewSessionUMASuffix));
   adapter_->InitializeNewSession(init_data_type_as_ascii,
                                  init_data,
                                  init_data_length,
                                  media::MediaKeys::TEMPORARY_SESSION,
                                  promise.Pass());
 }
 
 void WebContentDecryptionModuleSessionImpl::update(
     const uint8* response,
     size_t response_length,
@@ skipping 116 matching lines @@
 
 uint32 WebContentDecryptionModuleSessionImpl::AddResult(
     blink::WebContentDecryptionModuleResult result) {
   uint32 result_index = next_available_result_index_++;
   DCHECK(result_index != kReservedIndex);
   outstanding_results_.insert(std::make_pair(result_index, result));
   return result_index;
 }
 
 }  // namespace content