Enabled tests to control material design ink drop animations.

ui/views/animation/ink_drop_hover.cc

Index: ui/views/animation/ink_drop_hover.cc
diff --git a/ui/views/animation/ink_drop_hover.cc b/ui/views/animation/ink_drop_hover.cc
index 9bb7b02d8958015a3eedd6acc34b943d79d8d1ae..f53a95a0284184c0d1aa1ab8a1a171cdc6d110b3 100644
--- a/ui/views/animation/ink_drop_hover.cc
+++ b/ui/views/animation/ink_drop_hover.cc
@@ -59,6 +59,10 @@ void InkDropHover::FadeOut(const base::TimeDelta& duration, bool explode) {
   AnimateFade(FADE_OUT, duration, size_, explode ? explode_size_ : size_);
 }
 
+test::InkDropHoverTestApi* InkDropHover::GetTestApi() {
+  return nullptr;
+}
+
 void InkDropHover::AnimateFade(HoverAnimationType animation_type,
                                const base::TimeDelta& duration,
                                const gfx::Size& initial_size,