Prepare MediaDrmBridge to work with MediaCodecPlayer

media/base/browser_cdm.h

Index: media/base/browser_cdm.h
diff --git a/media/base/browser_cdm.h b/media/base/browser_cdm.h
index f4902d8708bc16253b40a52b1dac41db923cab9d..8b116e74680eca62faba84cae0f9bc8775e9d5b1 100644
--- a/media/base/browser_cdm.h
+++ b/media/base/browser_cdm.h
@@ -5,6 +5,7 @@
 #ifndef MEDIA_BASE_BROWSER_CDM_H_
 #define MEDIA_BASE_BROWSER_CDM_H_
 
+#include "base/memory/scoped_ptr.h"
 #include "media/base/media_export.h"
 #include "media/base/media_keys.h"
 #include "media/base/player_tracker.h"
@@ -16,6 +17,9 @@ class MEDIA_EXPORT BrowserCdm : public MediaKeys, public PlayerTracker {
  public:
   ~BrowserCdm() override;
 
+  // Virtual destructor. For most subclasses we can delete on the caller thread.
+  virtual void DeleteOnCorrectThread();
+
  protected:
    BrowserCdm();
 
@@ -23,6 +27,14 @@ class MEDIA_EXPORT BrowserCdm : public MediaKeys, public PlayerTracker {
   DISALLOW_COPY_AND_ASSIGN(BrowserCdm);
 };
 
+struct MEDIA_EXPORT BrowserCdmDeleter {
+  inline void operator()(BrowserCdm* ptr) const {
+    ptr->DeleteOnCorrectThread();
+  }
+};
+
+typedef scoped_ptr<BrowserCdm, BrowserCdmDeleter> BrowserCdmPtr;
+
 }  // namespace media
 
 #endif  // MEDIA_BASE_BROWSER_CDM_H_