diff --git a/mobile/android/base/animation/TransitionsTracker.java b/mobile/android/base/animation/TransitionsTracker.java
deleted file mode 100644
index 78672b9a18e9..000000000000
--- a/mobile/android/base/animation/TransitionsTracker.java
+++ /dev/null
@@ -1,119 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-package org.mozilla.gecko.animation;
-
-import com.nineoldandroids.animation.Animator;
-
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.List;
-
-import org.mozilla.gecko.animation.PropertyAnimator;
-import org.mozilla.gecko.animation.PropertyAnimator.PropertyAnimationListener;
-import org.mozilla.gecko.util.ThreadUtils;
-
-
-/**
- * {@link TransitionsTracker} provides a simple API to avoid running layout code
- * during UI transitions. You should use it whenever you need to time-shift code
- * that will likely trigger a layout traversal during an animation.
- */
-public class TransitionsTracker {
-    private static final ArrayList<Runnable> pendingActions = new ArrayList<>();
-    private static int transitionCount;
-
-    private static final PropertyAnimationListener propertyAnimatorListener =
-            new PropertyAnimationListener() {
-        @Override
-        public void onPropertyAnimationStart() {
-            pushTransition();
-        }
-
-        @Override
-        public void onPropertyAnimationEnd() {
-            popTransition();
-        }
-    };
-
-    private static final Animator.AnimatorListener animatorListener =
-            new Animator.AnimatorListener() {
-        @Override
-        public void onAnimationStart(Animator animation) {
-            pushTransition();
-        }
-
-        @Override
-        public void onAnimationEnd(Animator animation) {
-            popTransition();
-        }
-
-        @Override
-        public void onAnimationCancel(Animator animation) {
-        }
-
-        @Override
-        public void onAnimationRepeat(Animator animation) {
-        }
-    };
-
-    private static void runPendingActions() {
-        ThreadUtils.assertOnUiThread();
-
-        final int size = pendingActions.size();
-        for (int i = 0; i < size; i++) {
-            pendingActions.get(i).run();
-        }
-
-        pendingActions.clear();
-    }
-
-    public static void pushTransition() {
-        ThreadUtils.assertOnUiThread();
-        transitionCount++;
-    }
-
-    public static void popTransition() {
-        ThreadUtils.assertOnUiThread();
-        transitionCount--;
-
-        if (transitionCount < 0) {
-            throw new IllegalStateException("Invalid transition stack update");
-        }
-
-        if (transitionCount == 0) {
-            runPendingActions();
-        }
-    }
-
-    public static boolean areTransitionsRunning() {
-        ThreadUtils.assertOnUiThread();
-        return (transitionCount > 0);
-    }
-
-    public static void track(PropertyAnimator animator) {
-        ThreadUtils.assertOnUiThread();
-        animator.addPropertyAnimationListener(propertyAnimatorListener);
-    }
-
-    public static void track(Animator animator) {
-        ThreadUtils.assertOnUiThread();
-        animator.addListener(animatorListener);
-    }
-
-    public static boolean cancelPendingAction(Runnable action) {
-        ThreadUtils.assertOnUiThread();
-        return pendingActions.removeAll(Collections.singleton(action));
-    }
-
-    public static void runAfterTransitions(Runnable action) {
-        ThreadUtils.assertOnUiThread();
-
-        if (transitionCount == 0) {
-            action.run();
-        } else {
-            pendingActions.add(action);
-        }
-    }
-}
\ No newline at end of file
diff --git a/mobile/android/base/moz.build b/mobile/android/base/moz.build
index 083e6c105955..24f278eb0be4 100644
--- a/mobile/android/base/moz.build
+++ b/mobile/android/base/moz.build
@@ -436,7 +436,6 @@ gbjar.sources += [
     'toolbar/ToolbarPrefs.java',
     'toolbar/ToolbarProgressView.java',
     'TouchEventInterceptor.java',
-    'TransitionsTracker.java',
     'updater/UpdateService.java',
     'updater/UpdateServiceHelper.java',
     'Webapp.java',