Add content decryptor related structs and update PP{P|B}_ContentDecryptor_Private.

ppapi/api/private/ppb_content_decryptor_private.idl

Index: ppapi/api/private/ppb_content_decryptor_private.idl
diff --git a/ppapi/api/private/ppb_content_decryptor_private.idl b/ppapi/api/private/ppb_content_decryptor_private.idl
index 2a07eae83455e78d641e167dc62ca8f70aa56142..e155f26bbe4977b22d7d10b676ef041572ccc3b7 100644
--- a/ppapi/api/private/ppb_content_decryptor_private.idl
+++ b/ppapi/api/private/ppb_content_decryptor_private.idl
@@ -136,13 +136,13 @@ interface PPB_ContentDecryptor_Private {
    * <code>PPB_Buffer_Dev</code> resource that contains a decrypted data
    * block.
    *
-   * @param[in] request_id A unique value the browser can use to associate
-   * decrypted_block with a decrypt call.
+   * @param[in] tracking_info Tracking info the browser can use to associate
+   * decrypted_block with a decrypt call and/or an input (encrypted) buffer.
    */
   void DeliverBlock(
       [in] PP_Instance instance,
       [in] PP_Resource decrypted_block,
-      [in] int32_t request_id);
+      [in] PP_DecryptTrackingInfo tracking_info);
 
   /**
    * Called after the <code>DecryptAndDecode()</code> method on the
@@ -152,13 +152,13 @@ interface PPB_ContentDecryptor_Private {
    * @param[in] decrypted_frame A <code>PP_Resource</code> corresponding to a
    * <code>PPB_Buffer_Dev</code> resource that contains a video frame.
    *
-   * @param[in] request_id A unique value the browser can use to associate
-   * decrypted_frame with a decrypt call.
+   * @param[in] tracking_info Tracking info the browser can use to associate
+   * decrypted_block with a decrypt call and/or an input (encrypted) buffer.
    */
   void DeliverFrame(
       [in] PP_Instance instance,
       [in] PP_Resource decrypted_frame,
-      [in] int32_t request_id);
+      [in] PP_DecryptTrackingInfo tracking_info);
 
   /**
    * Called after the <code>DecryptAndDecode()</code> method on the
@@ -170,11 +170,11 @@ interface PPB_ContentDecryptor_Private {
    * <code>PPB_Buffer_Dev</code> resource that contains a decrypted buffer
    * of decoded audio samples.
    *
-   * @param[in] request_id A unique value the browser can use to associate
-   * decrypted_samples with a decrypt call.
+   * @param[in] tracking_info Tracking info the browser can use to associate
+   * decrypted_block with a decrypt call and/or an input (encrypted) buffer.
    */
   void DeliverSamples(
       [in] PP_Instance instance,
       [in] PP_Resource decrypted_samples,
-      [in] int32_t request_id);
+      [in] PP_DecryptTrackingInfo tracking_info);
 };