diff -r 000000000000 -r 6474c204b198 mobile/android/base/widget/ArrowPopup.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mobile/android/base/widget/ArrowPopup.java	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,129 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * 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.widget;
+
+import org.mozilla.gecko.GeckoApp;
+import org.mozilla.gecko.R;
+import org.mozilla.gecko.util.HardwareUtils;
+
+import android.content.res.Resources;
+import android.graphics.drawable.BitmapDrawable;
+import android.os.Build;
+import android.view.Gravity;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ImageView;
+import android.widget.LinearLayout;
+import android.widget.PopupWindow;
+import android.widget.RelativeLayout;
+
+public class ArrowPopup extends PopupWindow {
+    protected final GeckoApp mActivity;
+
+    private View mAnchor;
+    private ImageView mArrow;
+
+    private int mArrowWidth;
+    private int mYOffset;
+
+    protected LinearLayout mContent;
+    protected boolean mInflated;
+
+    public ArrowPopup(GeckoApp aActivity) {
+        this(aActivity, null);
+    }
+
+    public ArrowPopup(GeckoApp activity, View anchor) {
+        super(activity);
+        mActivity = activity;
+        mAnchor = anchor;
+
+        mInflated = false;
+
+        final Resources res = activity.getResources();
+        mArrowWidth = res.getDimensionPixelSize(R.dimen.menu_popup_arrow_width);
+        mYOffset = res.getDimensionPixelSize(R.dimen.menu_popup_arrow_offset);
+
+        setAnimationStyle(R.style.PopupAnimation);
+    }
+
+    public void setAnchor(View anchor) {
+        mAnchor = anchor;
+    }
+
+    protected void init() {
+        setBackgroundDrawable(new BitmapDrawable());
+        setOutsideTouchable(true);
+
+        setWindowLayoutMode(HardwareUtils.isTablet() ? ViewGroup.LayoutParams.WRAP_CONTENT : ViewGroup.LayoutParams.FILL_PARENT,
+            ViewGroup.LayoutParams.WRAP_CONTENT);
+
+        LayoutInflater inflater = LayoutInflater.from(mActivity);
+        RelativeLayout layout = (RelativeLayout) inflater.inflate(R.layout.arrow_popup, null);
+        setContentView(layout);
+
+        mArrow = (ImageView) layout.findViewById(R.id.arrow);
+        mContent = (LinearLayout) layout.findViewById(R.id.content);
+
+        mInflated = true;
+    }
+
+    /*
+     * Shows the popup with the arrow pointing to the center of the anchor view. If an anchor hasn't
+     * been set or isn't visible, the popup will just be shown at the top of the gecko app view.
+     */
+    public void show() {
+        int[] anchorLocation = new int[2];
+        if (mAnchor != null)
+            mAnchor.getLocationInWindow(anchorLocation);
+
+        // If there's no anchor or the anchor is out of the window bounds,
+        // just show the popup at the top of the gecko app view.
+        if (mAnchor == null || anchorLocation[1] < 0) {
+            final View view = mActivity.getView();
+
+            // Bug in android code causes the window layout parameters to be ignored
+            // when using showAtLocation() in Gingerbread phones.
+            if (Build.VERSION.SDK_INT < 11) {
+                setWidth(view.getWidth());
+                setHeight(view.getHeight());
+            }
+
+            showAtLocation(view, Gravity.TOP, 0, 0);
+            return;
+        }
+
+        // Remove padding from the width of the anchor when calculating the arrow offset.
+        int anchorWidth = mAnchor.getWidth() - mAnchor.getPaddingLeft() - mAnchor.getPaddingRight();
+        // This is the difference between the edge of the anchor view and the edge of the arrow view.
+        // We're making an assumption here that the anchor view is wider than the arrow view.
+        int arrowOffset = (anchorWidth - mArrowWidth)/2 + mAnchor.getPaddingLeft();
+
+        // The horizontal offset of the popup window, relative to the left side of the anchor view.
+        int offset = 0;
+
+        RelativeLayout.LayoutParams arrowLayoutParams = (RelativeLayout.LayoutParams) mArrow.getLayoutParams();
+
+        if (HardwareUtils.isTablet()) {
+            // On tablets, the popup has a fixed width, so we use a horizontal offset to position it.
+            // The arrow's left margin is set by the arrow_popup.xml layout file.
+            // This assumes that anchor is not too close to the right side of the screen.
+            offset = arrowOffset - arrowLayoutParams.leftMargin;
+        } else {
+            // On phones, the popup takes up the width of the screen, so we set the arrow's left
+            // margin to make it line up with the anchor.
+            int leftMargin = anchorLocation[0] + arrowOffset;
+            arrowLayoutParams.setMargins(leftMargin, 0, 0, 0);
+        }
+
+        if (isShowing()) {
+            update(mAnchor, offset, -mYOffset, -1, -1);
+        } else {
+            showAsDropDown(mAnchor, offset, -mYOffset);
+        }
+    }
+}