Check for no pixels after calling lockPixels(). If so, we return rather than

ui/gfx/color_utils.cc

Index: ui/gfx/color_utils.cc
===================================================================
--- ui/gfx/color_utils.cc	(revision 86420)
+++ ui/gfx/color_utils.cc	(working copy)
@@ -208,6 +208,9 @@
 
   SkAutoLockPixels favicon_lock(*favicon);
   SkColor* pixels = static_cast<SkColor*>(favicon->getPixels());
+  if (!pixels)
+    return SkColorSetARGB(alpha, 0, 0, 0);
+
   // Assume ARGB_8888 format.
   DCHECK(favicon->getConfig() == SkBitmap::kARGB_8888_Config);
   SkColor* current_color = pixels;
@@ -241,6 +244,9 @@
 
 void BuildLumaHistogram(SkBitmap* bitmap, int histogram[256]) {
   SkAutoLockPixels bitmap_lock(*bitmap);
+  if (!bitmap->getPixels())
+    return;
+
   // Assume ARGB_8888 format.
   DCHECK(bitmap->getConfig() == SkBitmap::kARGB_8888_Config);