Refactoring to make adding ink drop animations easier

ui/views/animation/ink_drop_host.h

Index: ui/views/animation/ink_drop_host.h
diff --git a/ui/views/animation/ink_drop_host.h b/ui/views/animation/ink_drop_host.h
index 4045e09d6c10c5a3ee6874d6d10350404c68ce31..6246d68d35ff6728b4b66df69aec71976074a74b 100644
--- a/ui/views/animation/ink_drop_host.h
+++ b/ui/views/animation/ink_drop_host.h
@@ -6,6 +6,7 @@
 #define UI_VIEWS_ANIMATION_INK_DROP_HOST_H_
 
 #include "base/macros.h"
+#include "ui/gfx/geometry/point.h"
 #include "ui/views/views_export.h"
 
 namespace ui {
@@ -32,6 +33,9 @@ class VIEWS_EXPORT InkDropHost {
   // Removes |ink_drop_layer| from the layer tree.
   virtual void RemoveInkDropLayer(ui::Layer* ink_drop_layer) = 0;
 
+  // Returns the Point where the ink drop should be centered.
+  virtual gfx::Point CalculateInkDropCenter() const = 0;

[bruthig, 2015/11/12 16:41:15]

Adding this here ties a host 1-to-1 with ripples. My thinking was the host
should only know how to add/remove layers and as such it would be possible to
host more than 1 ink drop.

I suggest moving this in to the InkDropConsumer class that I've defined in this
CL here: https://codereview.chromium.org/1390113006/

[varkha, 2015/11/13 00:32:42]

Added a TODO. I can change that once your CL lands.

+
  private:
   DISALLOW_COPY_AND_ASSIGN(InkDropHost);
 };