Add a PNGEncoder helper function that takes an SkBitmap,

chrome/browser/webdata/web_database.cc

Index: chrome/browser/webdata/web_database.cc
diff --git a/chrome/browser/webdata/web_database.cc b/chrome/browser/webdata/web_database.cc
old mode 100644
new mode 100755
index af78244326e29bfc5332e75ff82270d9f6adc3bd..83fa217cd32d5085f9cd55ef05baf2e4c2be99f7
--- a/chrome/browser/webdata/web_database.cc
+++ b/chrome/browser/webdata/web_database.cc
@@ -201,11 +201,7 @@ bool WebDatabase::SetWebAppImage(const GURL& url,
   }
 
   std::vector<unsigned char> image_data;
-
-  SkAutoLockPixels pixel_lock(image);
-  PNGEncoder::Encode(reinterpret_cast<unsigned char*>(image.getPixels()),
-                     PNGEncoder::FORMAT_BGRA, image.width(),
-                     image.height(), image.width() * 4, false, &image_data);
+  PNGEncoder::EncodeBGRASkBitmap(image, false, &image_data);
 
   s.bind_string(0, history::HistoryDatabase::GURLToDatabaseURL(url));
   s.bind_int(1, image.width());