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diff --git a/app/gfx/skbitmap_operations.h b/app/gfx/skbitmap_operations.h
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+// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef APP_GFX_SKBITMAP_OPERATIONS_H_
+#define APP_GFX_SKBITMAP_OPERATIONS_H_
+
+#include "app/gfx/color_utils.h"
+#include "testing/gtest/include/gtest/gtest_prod.h"
+
+class SkBitmap;
+
+class SkBitmapOperations {
+ public:
+  // Create a bitmap that is a blend of two others. The alpha argument
+  // specifies the opacity of the second bitmap. The provided bitmaps must
+  // use have the kARGB_8888_Config config and be of equal dimensions.
+  static SkBitmap CreateBlendedBitmap(const SkBitmap& first,
+                                      const SkBitmap& second,
+                                      double alpha);
+
+  // Create a bitmap that is the original bitmap masked out by the mask defined
+  // in the alpha bitmap. The images must use the kARGB_8888_Config config and
+  // be of equal dimensions.
+  static SkBitmap CreateMaskedBitmap(const SkBitmap& first,
+                                     const SkBitmap& alpha);
+
+  // We create a button background image by compositing the color and image
+  // together, then applying the mask. This is a highly specialized composite
+  // operation that is the equivalent of drawing a background in |color|,
+  // tiling |image| over the top, and then masking the result out with |mask|.
+  // The images must use kARGB_8888_Config config.
+  static SkBitmap CreateButtonBackground(SkColor color,
+                                         const SkBitmap& image,
+                                         const SkBitmap& mask);
+
+  // Shift a bitmap's HSL values. The shift values are in the range of 0-1,
+  // with the option to specify -1 for 'no change'. The shift values are
+  // defined as:
+  // hsl_shift[0] (hue): The absolute hue value for the image - 0 and 1 map
+  //    to 0 and 360 on the hue color wheel (red).
+  // hsl_shift[1] (saturation): A saturation shift for the image, with the
+  //    following key values:
+  //    0 = remove all color.
+  //    0.5 = leave unchanged.
+  //    1 = fully saturate the image.
+  // hsl_shift[2] (lightness): A lightness shift for the image, with the
+  //    following key values:
+  //    0 = remove all lightness (make all pixels black).
+  //    0.5 = leave unchanged.
+  //    1 = full lightness (make all pixels white).
+  static SkBitmap CreateHSLShiftedBitmap(const SkBitmap& bitmap,
+                                         color_utils::HSL hsl_shift);
+
+  // Create a bitmap that is cropped from another bitmap. This is special
+  // because it tiles the original bitmap, so your coordinates can extend
+  // outside the bounds of the original image.
+  static SkBitmap CreateTiledBitmap(const SkBitmap& bitmap,
+                                    int src_x, int src_y,
+                                    int dst_w, int dst_h);
+
+  // Iteratively downsamples by 2 until the bitmap is no smaller than the
+  // input size. The normal use of this is to downsample the bitmap "close" to
+  // the final size, and then use traditional resampling on the result.
+  // Because the bitmap will be closer to the final size, it will be faster,
+  // and linear interpolation will generally work well as a second step.
+  static SkBitmap DownsampleByTwoUntilSize(const SkBitmap& bitmap,
+                                           int min_w, int min_h);
+
+ private:
+  SkBitmapOperations();  // Class for scoping only.
+
+  // Makes a bitmap half has large in each direction by averaging groups of
+  // 4 pixels. This is one step in generating a mipmap.
+  static SkBitmap DownsampleByTwo(const SkBitmap& bitmap);
+
+  FRIEND_TEST(SkBitmapOperationsTest, DownsampleByTwo);
+  FRIEND_TEST(SkBitmapOperationsTest, DownsampleByTwoSmall);
+};
+
+#endif  // APP_GFX_SKBITMAP_OPERATIONS_H_
+