Center dino within the cleared area in generated sharing QR codes

Bug: 1107690
Change-Id: Ib94f111c3f4080c658f37dd8f25a4d8da751d5a2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2354905
Auto-Submit: Avi Drissman <avi@chromium.org>
Commit-Queue: Travis Skare <skare@chromium.org>
Reviewed-by: Travis Skare <skare@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797980}

chrome/services/qrcode_generator/qrcode_generator_service_impl.cc

@@ -104,8 +104,14 @@ void QRCodeGeneratorServiceImpl::DrawDino(SkCanvas* canvas,
           kModuleSizePixels * kModuleSizePixels,
       (dest_rect.bottom() + dino_border_px + kModuleSizePixels - 1) /
           kModuleSizePixels * kModuleSizePixels);
-
   canvas->drawRect(background, paint_background);
+
+  // Center the dino within the cleared space, and draw it.
+  SkScalar delta_x =
+      SkScalarRoundToScalar(background.centerX() - dest_rect.centerX());
+  SkScalar delta_y =
+      SkScalarRoundToScalar(background.centerY() - dest_rect.centerY());
+  dest_rect.offset(delta_x, delta_y);
   SkRect dino_bounds;
   dino_bitmap_.getBounds(&dino_bounds);
   canvas->drawBitmapRect(dino_bitmap_, dino_bounds, dest_rect, nullptr);