Centered flood fill style ink drop ripples on mouse/touch points.

ui/gfx/geometry/rect.cc

Index: ui/gfx/geometry/rect.cc
diff --git a/ui/gfx/geometry/rect.cc b/ui/gfx/geometry/rect.cc
index e7a3aa2aac93f14eb96c4832a130f4bbeafa9253..b7bdc3947d57f14d6dd168adbe4cd5867d982d49 100644
--- a/ui/gfx/geometry/rect.cc
+++ b/ui/gfx/geometry/rect.cc
@@ -239,6 +239,19 @@ int Rect::ManhattanInternalDistance(const Rect& rect) const {
   return x + y;
 }
 
+float Rect::MaxDistanceToCorners(const gfx::Point& point) const {
+  const float distance_to_top_left = (origin() - point).Length();
+  const float distance_to_top_right = (top_right() - point).Length();
+  const float distance_to_bottom_left = (bottom_left() - point).Length();
+  const float distance_to_bottom_right = (bottom_right() - point).Length();
+
+  float largest_distance =
+      std::max(distance_to_top_left, distance_to_top_right);
+  largest_distance = std::max(largest_distance, distance_to_bottom_left);
+  largest_distance = std::max(largest_distance, distance_to_bottom_right);
+  return largest_distance;
+}
+
 std::string Rect::ToString() const {
   return base::StringPrintf("%s %s",
                             origin().ToString().c_str(),