Coordinators are now notified when moving to a parent coordinator.

ios/clean/chrome/browser/browser_coordinator+internal.h

Index: ios/clean/chrome/browser/browser_coordinator+internal.h
diff --git a/ios/clean/chrome/browser/browser_coordinator+internal.h b/ios/clean/chrome/browser/browser_coordinator+internal.h
index 06315554a0e069006b5df9a7d672015fffd654f5..1a7fb15e9781b7e3eaa16ff6209f2451fdd9d0c3 100644
--- a/ios/clean/chrome/browser/browser_coordinator+internal.h
+++ b/ios/clean/chrome/browser/browser_coordinator+internal.h
@@ -55,6 +55,11 @@
 // |coordinator| isn't a child of the receiver, this method does nothing.
 - (void)removeChildCoordinator:(BrowserCoordinator*)coordinator;
 
+// Called when this coordinator moves to a new parent coordinator.  Subclasses
+// can override this method to run code that requires a configured
+// CoordinatorContext.
+- (void)coordinatorDidMoveToParentCoordinator;

[lpromero, 2017/03/15 12:15:08]

Note that I don't pass the parentCoordinator anymore. The receiver can ask for
its parentCoordinator directly.

+
 // Called when a child coordinator did start. This is a blank template method.
 // Subclasses can override this method when they need to know when their
 // children start.