diff -r 000000000000 -r 6474c204b198 build/mobile/robocop/PaintedSurface.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/build/mobile/robocop/PaintedSurface.java	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,105 @@
+/* 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;
+
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.nio.MappedByteBuffer;
+import java.nio.channels.FileChannel;
+
+import android.graphics.Bitmap;
+import android.util.Base64;
+import android.util.Base64OutputStream;
+
+public class PaintedSurface {
+    private String mFileName;
+    private int mWidth;
+    private int mHeight;
+    private FileInputStream mPixelFile;
+    private MappedByteBuffer mPixelBuffer;
+
+    public PaintedSurface(String filename, int width, int height) {
+        mFileName = filename;
+        mWidth = width;
+        mHeight = height;
+
+        try {
+            File f = new File(filename);
+            int pixelSize = (int)f.length();
+
+            mPixelFile = new FileInputStream(filename);
+            mPixelBuffer = mPixelFile.getChannel().map(FileChannel.MapMode.READ_ONLY, 0, pixelSize);
+        } catch (java.io.FileNotFoundException e) {
+            FennecNativeDriver.log(FennecNativeDriver.LogLevel.ERROR, e);
+        } catch (java.io.IOException e) {
+            FennecNativeDriver.log(FennecNativeDriver.LogLevel.ERROR, e);
+        }
+    }
+
+    public final int getWidth() {
+        return mWidth;
+    }
+
+    public final int getHeight() {
+        return mHeight;
+    }
+
+    private int pixelAtIndex(int index) {
+        int b1 = mPixelBuffer.get(index) & 0xFF;
+        int b2 = mPixelBuffer.get(index + 1) & 0xFF;
+        int b3 = mPixelBuffer.get(index + 2) & 0xFF;
+        int b4 = mPixelBuffer.get(index + 3) & 0xFF;
+        int value = (b1 << 24) + (b2 << 16) + (b3 << 8) + (b4 << 0);
+        return value;
+    }
+
+    public final int getPixelAt(int x, int y) {
+        if (mPixelBuffer == null) {
+            throw new RoboCopException("Trying to access PaintedSurface with no active PixelBuffer");
+        }
+
+        if (x >= mWidth || x < 0) {
+            throw new RoboCopException("Trying to access PaintedSurface with invalid x value");
+        }
+
+        if (y >= mHeight || y < 0) {
+            throw new RoboCopException("Trying to access PaintedSurface with invalid y value");
+        }
+
+        // The rows are reversed so row 0 is at the end and we start with the last row.
+        // This is why we do mHeight-y;
+        int index = (x + ((mHeight - y - 1) * mWidth)) * 4;
+        return pixelAtIndex(index);
+    }
+
+    public final String asDataUri() {
+        try {
+            Bitmap bm = Bitmap.createBitmap(mWidth, mHeight, Bitmap.Config.ARGB_8888);
+            for (int y = 0; y < mHeight; y++) {
+                for (int x = 0; x < mWidth; x++) {
+                    int index = (x + ((mHeight - y - 1) * mWidth)) * 4;
+                    bm.setPixel(x, y, pixelAtIndex(index));
+                }
+            }
+            ByteArrayOutputStream out = new ByteArrayOutputStream();
+            out.write("data:image/png;base64,".getBytes());
+            Base64OutputStream b64 = new Base64OutputStream(out, Base64.NO_WRAP);
+            bm.compress(Bitmap.CompressFormat.PNG, 100, b64);
+            return new String(out.toByteArray());
+        } catch (Exception e) {
+            FennecNativeDriver.log(FennecNativeDriver.LogLevel.ERROR, e);
+            throw new RoboCopException("Unable to convert surface to a PNG data:uri");
+        }
+    }
+
+    public void close() {
+        try {
+            mPixelFile.close();
+        } catch (Exception e) {
+            FennecNativeDriver.log(FennecNativeDriver.LogLevel.DEBUG, e);
+        }
+    }
+}