Ensure there are always nice icons for bookmark apps.

extensions/common/image_util.cc

Index: extensions/common/image_util.cc
diff --git a/extensions/browser/image_util.cc b/extensions/common/image_util.cc
similarity index 82%
rename from extensions/browser/image_util.cc
rename to extensions/common/image_util.cc
index 2454a632fee850b4bcb51b22314d1808921670f3..4b16367fd96de9ba1d8e7c93b29a3fcc433ba610 100644
--- a/extensions/browser/image_util.cc
+++ b/extensions/common/image_util.cc
@@ -2,12 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "extensions/browser/image_util.h"
+#include "extensions/common/image_util.h"
 
 #include <stdint.h>
 #include <vector>
 
 #include "base/strings/string_number_conversions.h"
+#include "base/strings/stringprintf.h"
 #include "third_party/skia/include/core/SkColor.h"
 
 namespace extensions {
@@ -41,5 +42,10 @@ bool ParseCSSColorString(const std::string& color_string, SkColor* result) {
   return true;
 }
 
+std::string GenerateCSSColorString(SkColor color) {
+  return base::StringPrintf("#%02X%02X%02X", SkColorGetR(color),
+                            SkColorGetG(color), SkColorGetB(color));
+}
+
 }  // namespace image_util
 }  // namespace extensions