RefCounted types should not have public destructors, delegate cleanup

For Delegate/Observer-type classes that specify an
interface but do not have any particular lifetime
requirements, make their destructors protected. This is to
allow their interfaces to be implemented safely by
RefCounted types. With public destructors, it's possible to
do "scoped_ptr<Delegate> foo", and then assign a
RefCountedDelegateImpl, which would lead to a double free.

As none of these Delegates actually need public destructors
(ownership of the Delegate* is not transferred during a
function call / class constructor), mark the destructors
protected so that it becomes a compile warning to try to
delete them via the Delegate*.

BUG=123295
TEST=it compiles


Review URL: https://chromiumcodereview.appspot.com/10383262

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@144086 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 3 insertions, 2 deletions

diff --git a/media/base/demuxer.h b/media/base/demuxer.h
index 48d0e6a..3fdc37b 100644
--- a/media/base/demuxer.h
+++ b/media/base/demuxer.h
@@ -16,8 +16,6 @@ namespace media {
 
 class MEDIA_EXPORT DemuxerHost : public DataSourceHost {
  public:
-  virtual ~DemuxerHost();
-
   // Sets the duration of the media in microseconds.
   // Duration may be kInfiniteDuration() if the duration is not known.
   virtual void SetDuration(base::TimeDelta duration) = 0;
@@ -25,6 +23,9 @@ class MEDIA_EXPORT DemuxerHost : public DataSourceHost {
   // Stops execution of the pipeline due to a fatal error.  Do not call this
   // method with PIPELINE_OK.
   virtual void OnDemuxerError(PipelineStatus error) = 0;
+
+ protected:
+  virtual ~DemuxerHost();
 };
 
 class MEDIA_EXPORT Demuxer : public base::RefCountedThreadSafe<Demuxer> {