diff -r 000000000000 -r 6474c204b198 mobile/android/base/tests/testThumbnails.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mobile/android/base/tests/testThumbnails.java	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,111 @@
+package org.mozilla.gecko.tests;
+
+import org.mozilla.gecko.db.BrowserDB;
+
+import android.content.ContentResolver;
+import android.graphics.Color;
+
+/**
+ * Test for thumbnail updates.
+ * - loads 2 pages, each of which yield an HTTP 200
+ * - verifies thumbnails are updated for both pages
+ * - loads pages again; first page yields HTTP 200, second yields HTTP 404
+ * - verifies thumbnail is updated for HTTP 200, but not HTTP 404
+ * - finally, test that BrowserDB.removeThumbnails drops the thumbnails
+ */
+public class testThumbnails extends BaseTest {
+    public void testThumbnails() {
+        final String site1Url = getAbsoluteUrl("/robocop/robocop_404.sjs?type=changeColor");
+        final String site2Url = getAbsoluteUrl("/robocop/robocop_404.sjs?type=do404");
+        final String site1Title = "changeColor";
+        final String site2Title = "do404";
+
+        // the session snapshot runnable is run 500ms after document stop. a
+        // 3000ms delay gives us 2.5 seconds to take the screenshot, which
+        // should be plenty of time, even on slow devices
+        final int thumbnailDelay = 3000;
+
+        blockForGeckoReady();
+
+        // load sites; both will return HTTP 200 with a green background
+        inputAndLoadUrl(site1Url);
+        mSolo.sleep(thumbnailDelay);
+        inputAndLoadUrl(site2Url);
+        mSolo.sleep(thumbnailDelay);
+        inputAndLoadUrl("about:home");
+        waitForTest(new ThumbnailTest(site1Title, Color.GREEN), 5000);
+        mAsserter.is(getTopSiteThumbnailColor(site1Title), Color.GREEN, "Top site thumbnail updated for HTTP 200");
+        waitForTest(new ThumbnailTest(site2Title, Color.GREEN), 5000);
+        mAsserter.is(getTopSiteThumbnailColor(site2Title), Color.GREEN, "Top site thumbnail updated for HTTP 200");
+
+        // load sites again; both will have red background, and do404 will return HTTP 404
+        inputAndLoadUrl(site1Url);
+        mSolo.sleep(thumbnailDelay);
+        inputAndLoadUrl(site2Url);
+        mSolo.sleep(thumbnailDelay);
+        inputAndLoadUrl("about:home");
+        waitForTest(new ThumbnailTest(site1Title, Color.RED), 5000);
+        mAsserter.is(getTopSiteThumbnailColor(site1Title), Color.RED, "Top site thumbnail updated for HTTP 200");
+        waitForTest(new ThumbnailTest(site2Title, Color.GREEN), 5000);
+        mAsserter.is(getTopSiteThumbnailColor(site2Title), Color.GREEN, "Top site thumbnail not updated for HTTP 404");
+
+        // test dropping thumbnails
+        final ContentResolver resolver = getActivity().getContentResolver();
+        // check that the thumbnail is non-null
+        byte[] thumbnailData = BrowserDB.getThumbnailForUrl(resolver, site1Url);
+        mAsserter.ok(thumbnailData != null && thumbnailData.length > 0, "Checking for thumbnail data", "No thumbnail data found");
+        // drop thumbnails
+        BrowserDB.removeThumbnails(resolver);
+        // check that the thumbnail is now null
+        thumbnailData = BrowserDB.getThumbnailForUrl(resolver, site1Url);
+        mAsserter.ok(thumbnailData == null || thumbnailData.length == 0, "Checking for thumbnail data", "Thumbnail data found");
+    }
+
+    private class ThumbnailTest implements BooleanTest {
+        private String mTitle;
+        private int mColor;
+
+        public ThumbnailTest(String title, int color) {
+            mTitle = title;
+            mColor = color;
+        }
+
+        @Override
+        public boolean test() {
+            return getTopSiteThumbnailColor(mTitle) == mColor;
+        }
+    }
+
+    private int getTopSiteThumbnailColor(String title) {
+        // This test is not currently run, so this just needs to compile.
+        return -1;
+//        ViewGroup topSites = (ViewGroup) getActivity().findViewById(mTopSitesId);
+//        if (topSites != null) {
+//            final int childCount = topSites.getChildCount();
+//            for (int i = 0; i < childCount; i++) {
+//                View child = topSites.getChildAt(i);
+//                if (child != null) {
+//                    TextView titleView = (TextView) child.findViewById(R.id.title);
+//                    if (titleView != null) {
+//                        if (titleView.getText().equals(title)) {
+//                            ImageView thumbnailView = (ImageView) child.findViewById(R.id.thumbnail);
+//                            if (thumbnailView != null) {
+//                                Bitmap thumbnail = ((BitmapDrawable) thumbnailView.getDrawable()).getBitmap();
+//                                return thumbnail.getPixel(0, 0);
+//                            } else {
+//                                mAsserter.dumpLog("getTopSiteThumbnailColor: unable to find mThumbnailId: "+R.id.thumbnail);
+//                            }
+//                        }
+//                    } else {
+//                        mAsserter.dumpLog("getTopSiteThumbnailColor: unable to find R.id.title: "+R.id.title);
+//                    }
+//                } else {
+//                    mAsserter.dumpLog("getTopSiteThumbnailColor: skipped null child at index "+i);
+//                }
+//            }
+//        } else {
+//            mAsserter.dumpLog("getTopSiteThumbnailColor: unable to find mTopSitesId: " + mTopSitesId);
+//        }
+//        return -1;
+    }
+}