editor+runtime: fix slow hit-testing

turns out forEachChild + recursion is a bad combo. Recurse on just the first level of the hierarchy. I also made sure that the `forEachChild` in both Dart and C++ would do the same thing, and have the same signature.

Diffs=
90da85fbb4 editor+runtime: fix slow hit-testing (#8907)

Co-authored-by: Susan Wang <[email protected]>

.rive_head

@@ -1 +1 @@
-b03d365c93d0d52f0f05ae598deacbf7dd330a53
+90da85fbb4151a7a4a1c30cf2f6738929debe925

include/rive/container_component.hpp

@@ -13,10 +13,12 @@ class ContainerComponent : public ContainerComponentBase
     virtual void addChild(Component* component);
     bool collapse(bool value) override;
 
-    // Returns true if it searched through all of its children. predicate can
-    // return false to stop searching.
+    // Returns whether predicate returns true for the current Component.
     bool forAll(std::function<bool(Component*)> predicate);
-    bool forEachChild(std::function<bool(Component*)> predicate);
+
+    // Recursively descend onto all the children in the hierarchy tree.
+    // If predicate returns false, it won't recurse down a particular branch.
+    void forEachChild(std::function<bool(Component*)> predicate);
 
 private:
     std::vector<Component*> m_children;

src/animation/state_machine_instance.cpp

@@ -1220,7 +1220,7 @@ void StateMachineInstance::addToHitLookup(
                            hitLookup,
                            listenerGroup,
                            isOpaque);
-            return true;
+            return false;
         });
         return;
     }

src/container_component.cpp

@@ -29,19 +29,17 @@ bool ContainerComponent::forAll(std::function<bool(Component*)> predicate)
     return true;
 }
 
-bool ContainerComponent::forEachChild(std::function<bool(Component*)> predicate)
+void ContainerComponent::forEachChild(std::function<bool(Component*)> predicate)
 {
     for (Component* child : m_children)
     {
         if (!predicate(child))
         {
-            return false;
+            continue;
         }
-        if (child->is<ContainerComponent>() &&
-            !child->as<ContainerComponent>()->forEachChild(predicate))
+        if (child->is<ContainerComponent>())
         {
-            return false;
+            child->as<ContainerComponent>()->forEachChild(predicate);
         }
     }
-    return true;
 }