[Android] Add animation frame time histogram class.

chrome/android/java/src/org/chromium/chrome/browser/appmenu/AppMenu.java

Index: chrome/android/java/src/org/chromium/chrome/browser/appmenu/AppMenu.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/appmenu/AppMenu.java b/chrome/android/java/src/org/chromium/chrome/browser/appmenu/AppMenu.java
index e4aa4b7417ea1a223ad2e0dc90dbd5b6de175f21..35246d558ff141587358ac9e86833f5a5d7b6ced 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/appmenu/AppMenu.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/appmenu/AppMenu.java
@@ -5,6 +5,7 @@
 package org.chromium.chrome.browser.appmenu;
 
 import android.animation.Animator;
+import android.animation.Animator.AnimatorListener;
 import android.animation.AnimatorSet;
 import android.content.Context;
 import android.content.res.Resources;
@@ -25,6 +26,7 @@ import android.widget.ListPopupWindow;
 import android.widget.PopupWindow;
 import android.widget.PopupWindow.OnDismissListener;
 
+import org.chromium.base.AnimationFrameTimeHistogram;
 import org.chromium.base.SysUtils;
 import org.chromium.chrome.R;
 
@@ -336,6 +338,30 @@ public class AppMenu implements OnItemClickListener, OnKeyListener {
             }
         }
 
+        animation.addListener(new AnimatorListener() {

[David Trainor- moved to gerrit, 2015/02/23 18:20:35]

AnimatorListenerAdapter then don't include onAnimationRepeat?

[Kibeom Kim (inactive), 2015/02/23 22:17:29]

Done.

+            private final AnimationFrameTimeHistogram mAnimationFrameTimeHistogram =
+                    new AnimationFrameTimeHistogram("WrenchMenu.OpeningAnimationFrameTimes");

[aurimas (slooooooooow), 2015/02/23 18:03:59]

Android strongly suggests against new object creation during draw/animation.
This would be violating that, right?

[David Trainor- moved to gerrit, 2015/02/23 18:20:35]

You're right, but I think they're more concerned with creating objects in the
draw/animation path that runs every frame.  This will be created at the same
time we create the AnimatorSet() above and roughly at the same time we create
all the other sub-animations, so we'll be doing a lot of allocations here anyway
that we have to do.

That said, I'm all for caching this listener if possible!

[Kibeom Kim (inactive), 2015/02/23 22:17:29]

Done.

+
+            @Override
+            public void onAnimationStart(Animator animation) {
+                mAnimationFrameTimeHistogram.startRecording();

[aurimas (slooooooooow), 2015/02/23 18:03:59]

How cheap is this call?

[Kibeom Kim (inactive), 2015/02/23 18:27:24]

I just measured 3 times, release build:

1st run:
onAnimationStart : 0.366245 ms
onAnimationEnd : 0.213642 ms

2nd run:
onAnimationStart : 0.03052 ms
onAnimationEnd : 0.122082 ms

3rd run:
onAnimationStart : 0.03052 ms
onAnimationEnd : 0.091561 ms

Also measured AnimationFrameTimeHistogram#Recorder#doFrame(...) but that's like
0, as expected.

+            }
+
+            @Override
+            public void onAnimationRepeat(Animator animation) {
+            }
+
+            @Override
+            public void onAnimationEnd(Animator animation) {
+                mAnimationFrameTimeHistogram.endRecording();
+            }
+
+            @Override
+            public void onAnimationCancel(Animator animation) {
+                mAnimationFrameTimeHistogram.endRecording();
+            }
+        });
+
         animation.start();
     }
 }