[IndexedDB] Adding transaction and value support to observers

content/browser/indexed_db/indexed_db_connection.h

Index: content/browser/indexed_db/indexed_db_connection.h
diff --git a/content/browser/indexed_db/indexed_db_connection.h b/content/browser/indexed_db/indexed_db_connection.h
index 20acb7b7244c0ed10041c8a59b955c37bf2c2419..d0828a931bbac1de3c0f0008daa70bf44ad41369 100644
--- a/content/browser/indexed_db/indexed_db_connection.h
+++ b/content/browser/indexed_db/indexed_db_connection.h
@@ -77,9 +77,17 @@ class CONTENT_EXPORT IndexedDBConnection {
   // TODO(dmurph): Change that so this doesn't need to ignore unknown ids.
   void RemoveTransaction(int64_t id);
 
+  // Returns a new transaction id for an observer transaction.
+  // Unique per connection.
+  int64_t NewObserverTransactionId();
+
  private:
   const int32_t id_;
 
+  // The renderer-created transactions are in the right 32 bits, and the
+  // browser-created transactions are in the left 32 bits.
+  int64_t next_observer_transaction_id_ = 1ll << 32;
+
   // The process id of the child process this connection is associated with.
   // Tracked for IndexedDBContextImpl::GetAllOriginsDetails and debugging.
   const int child_process_id_;