Changing multiprocess test SpawnChild to return a struct.

base/win/wait_chain_unittest.cc

Index: base/win/wait_chain_unittest.cc
diff --git a/base/win/wait_chain_unittest.cc b/base/win/wait_chain_unittest.cc
index ba04872206d561234436fc6a344d339bce8727db..d5814916150fa4bf36a0b73499f20036cd16c54f 100644
--- a/base/win/wait_chain_unittest.cc
+++ b/base/win/wait_chain_unittest.cc
@@ -194,7 +194,9 @@ Process StartChildProcess(HANDLE mutex, HANDLE sync_event) {
   handle_vector.push_back(mutex);
   handle_vector.push_back(sync_event);
   options.handles_to_inherit = &handle_vector;
-  return SpawnMultiProcessTestChild("WaitChainTestProc", command_line, options);
+  base::SpawnChildResult spawn_result =
+      SpawnMultiProcessTestChild("WaitChainTestProc", command_line, options);
+  return std::move(spawn_result.process);
 }
 
 // Returns true if the |wait_chain| is an alternating sequence of thread objects