Flip unified media pipeline to default-on w/ disabled holdback.

media/base/media.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/base/media.h"
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/macros.h"
 #include "base/metrics/field_trial.h"
@@ skipping 82 matching lines @@
 
 bool IsUnifiedMediaPipelineEnabled() {
   // TODO(dalecurtis): This experiment is temporary and should be removed once
   // we have enough data to support the primacy of the unified media pipeline;
   // see http://crbug.com/533190 for details.
   //
   // Note: It's important to query the field trial state first, to ensure that
   // UMA reports the correct group.
   const std::string group_name =
       base::FieldTrialList::FindFullName("UnifiedMediaPipelineTrial");
-  const bool enabled_via_cli =
+  const bool disabled_via_cli =
       base::CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kEnableUnifiedMediaPipeline);
+          switches::kDisableUnifiedMediaPipeline);
   // TODO(watk, dalecurtis): AVDA has bugs on API level 16 and 17 so it's
   // disabled for now. http://crbug.com/597467
   const bool api_level_supported =
       base::android::BuildInfo::GetInstance()->sdk_int() >= 18;
 
-  return enabled_via_cli || (api_level_supported &&
-                             base::StartsWith(group_name, "Enabled",
-                                              base::CompareCase::SENSITIVE));
+  return !disabled_via_cli && api_level_supported &&
+         !base::StartsWith(group_name, "Disabled",

[ddorwin, 2016/03/30 20:16:24]

Do all users already have "Enabled" or "Disabled" set? IOW, this doesn't depend
on a similar switch on the server.

[DaleCurtis, 2016/03/31 22:10:33]

The groups are, "Control", "Enabled", "EnabledByFlag", and "Disabled". The
currently meaning in the trial config is opposite of what this change does, but
I'll flip that once we have launch approval.

+                           base::CompareCase::SENSITIVE);
 }
 
 bool ArePlatformDecodersAvailable() {
   return IsUnifiedMediaPipelineEnabled()
              ? HasPlatformDecoderSupport()
              : MediaCodecUtil::IsMediaCodecAvailable();
 }
 #endif
 
 }  // namespace media