Adding ripple effect for clicks on MD slider

ui/views/controls/slider.cc

Index: ui/views/controls/slider.cc
diff --git a/ui/views/controls/slider.cc b/ui/views/controls/slider.cc
index dd1148ff1a59123e6f2c960404aee5ffe732267c..8ba08edb9e4c80eb1afb30c1bb1ac0aacef177db 100644
--- a/ui/views/controls/slider.cc
+++ b/ui/views/controls/slider.cc
@@ -176,6 +176,10 @@ float Slider::GetAnimatingValue() const{
              : value_;
 }
 
+void Slider::SetHighlighted(bool focus) {
+  return;

[bruthig, 2016/09/22 21:05:24]

nit: Remove

[yiyix, 2016/09/23 20:35:37]

Highlight needs a default implementation, so non_md_slider does not need to
implement this function. I originally have "virtual void SetHighlighted(bool
focus){};" and you asked me to move it to cc file. So does it mean that i should
have it in the .h file?

[bruthig, 2016/09/23 22:24:39]

I was just asking you to remove the return; statement.

+}
+
 bool Slider::OnMousePressed(const ui::MouseEvent& event) {
   if (!event.IsOnlyLeftMouseButton())
     return false;
@@ -207,11 +211,13 @@ bool Slider::OnKeyPressed(const ui::KeyEvent& event) {
 }
 
 void Slider::OnFocus() {
+  SetHighlighted(true);
   View::OnFocus();
   SchedulePaint();
 }
 
 void Slider::OnBlur() {
+  SetHighlighted(false);
   View::OnBlur();
   SchedulePaint();
 }
@@ -241,8 +247,12 @@ void Slider::OnGestureEvent(ui::GestureEvent* event) {
 }
 
 void Slider::AnimationProgressed(const gfx::Animation* animation) {
-  animating_value_ = animation->CurrentValueBetween(animating_value_, value_);
-  SchedulePaint();
+  if (move_animation_.get() && (animation == move_animation_.get())) {

[bruthig, 2016/09/22 21:05:24]

nit: Checking that |move_animation_| here is redundant.  I think it's safe to
assume |animation| will never be null.

+    float old_animating_value = animating_value_;
+    animating_value_ = animation->CurrentValueBetween(animating_value_, value_);
+    if (animating_value_ != old_animating_value)
+      SchedulePaint();
+  }
 }
 
 void Slider::GetAccessibleState(ui::AXViewState* state) {
@@ -253,11 +263,13 @@ void Slider::GetAccessibleState(ui::AXViewState* state) {
 }
 
 void Slider::OnSliderDragStarted() {
+  SetHighlighted(true);
   if (listener_)
     listener_->SliderDragStarted(this);
 }
 
 void Slider::OnSliderDragEnded() {
+  SetHighlighted(false);
   if (listener_)
     listener_->SliderDragEnded(this);
 }