Fix bug skipping certain animations from ending

endAnimations forces an end to all running animations. This also removes
it from the list which changes the list while we're iterating over it.
This fixes the issue.

Bug: 132285006
Test: Manual test w/ build forcing endAnimations
Change-Id: I0ee9917866dafe00ef3122dd9a43259d19fb9f79
diff --git a/go/quickstep/src/com/android/quickstep/ContentFillItemAnimator.java b/go/quickstep/src/com/android/quickstep/ContentFillItemAnimator.java
index 9282345..87ae695 100644
--- a/go/quickstep/src/com/android/quickstep/ContentFillItemAnimator.java
+++ b/go/quickstep/src/com/android/quickstep/ContentFillItemAnimator.java
@@ -250,7 +250,7 @@
             }
             mPendingAnims.remove(i);
         }
-        for (int i = 0; i < mRunningAnims.size(); i++) {
+        for (int i = mRunningAnims.size() - 1; i >= 0; i--) {
             ObjectAnimator anim = mRunningAnims.get(i);
             anim.end();
         }