[animations] Adds metrics for jank on selected layer animations

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 00516232f1f909153184acf573263a89bae8a4dc..5023325f29e1c8a0062181160f346457460135d1 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -2131,6 +2131,33 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Ash.WindowSelector.AnimationSmoothness.Close" units="%">
+  <owner>varkha@chromium.org</owner>
+  <owner>tdanderson@chromium.org</owner>
+  <summary>
+    Relative smoothness of animations when closing a window in overview mode.
+    100% represents ideally smooth 60 frames per second.
+  </summary>
+</histogram>
+
+<histogram name="Ash.WindowSelector.AnimationSmoothness.Enter" units="%">
+  <owner>varkha@chromium.org</owner>
+  <owner>tdanderson@chromium.org</owner>
+  <summary>
+    Relative smoothness of animations when entering overview mode. 100%
+    represents ideally smooth 60 frames per second.
+  </summary>
+</histogram>
+
+<histogram name="Ash.WindowSelector.AnimationSmoothness.Exit" units="%">
+  <owner>varkha@chromium.org</owner>
+  <owner>tdanderson@chromium.org</owner>
+  <summary>
+    Relative smoothness of animations when exiting overview mode. 100%
+    represents ideally smooth 60 frames per second.
+  </summary>
+</histogram>
+
 <histogram name="Ash.WindowSelector.ArrowKeyPresses">
   <owner>flackr@chromium.org</owner>
   <owner>tdanderson@chromium.org</owner>
@@ -72157,6 +72184,26 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Views.AnimationSmoothness.FloodFillRipple" units="%">
+  <owner>varkha@chromium.org</owner>
+  <owner>bruthig@chromium.org</owner>
+  <summary>
+    Relative smoothness of animations when clicking or touching a rectangular
+    button that has a flood-fill ink drop ripple effect. 100% represents ideally
+    smooth 60 frames per second.
+  </summary>
+</histogram>
+
+<histogram name="Views.AnimationSmoothness.SquareRipple" units="%">
+  <owner>varkha@chromium.org</owner>
+  <owner>bruthig@chromium.org</owner>
+  <summary>
+    Relative smoothness of animations when clicking or touching a square button.
+    that has a circle ink drop ripple effect. 100% represents ideally smooth 60
+    frames per second.
+  </summary>
+</histogram>
+
 <histogram name="VirtualKeyboard.KeyboardControlEvent"
     enum="KeyboardControlEvent">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>