Enabled tests to control material design ink drop animations.

ui/views/animation/ink_drop_animation.cc

Index: ui/views/animation/ink_drop_animation.cc
diff --git a/ui/views/animation/ink_drop_animation.cc b/ui/views/animation/ink_drop_animation.cc
index 717b905ee7eb475e99de211f679bc63db6aa2c45..214716da23aeec8c87f7ce62b08bc9931fbd78ed 100644
--- a/ui/views/animation/ink_drop_animation.cc
+++ b/ui/views/animation/ink_drop_animation.cc
@@ -91,6 +91,10 @@ void InkDropAnimation::HideImmediately() {
   target_ink_drop_state_ = InkDropState::HIDDEN;
 }
 
+test::InkDropAnimationTestApi* InkDropAnimation::GetTestApi() {
+  return nullptr;
+}
+
 void InkDropAnimation::AnimationStartedCallback(
     InkDropState ink_drop_state,
     const ui::CallbackLayerAnimationObserver& observer) {