[Android] Add a native pull-to-refresh overscroll effect

ui/android/java/src/org/chromium/ui/gfx/BitmapHelper.java

 // Copyright 2012 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.
 
 package org.chromium.ui.gfx;
 
-import android.content.res.Resources;
 import android.graphics.Bitmap;
-import android.graphics.BitmapFactory;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
 
 /**
  * Helper class to decode and sample down bitmap resources.
  */
 @JNINamespace("gfx")
 public class BitmapHelper {
     @CalledByNative
     private static Bitmap createBitmap(int width,
                                       int height,
                                       int bitmapFormatValue) {
         Bitmap.Config bitmapConfig = getBitmapConfigForFormat(bitmapFormatValue);
         return Bitmap.createBitmap(width, height, bitmapConfig);
     }
 
     /**
-     * Decode and sample down a bitmap resource to the requested width and height.
-     *
-     * @param name The resource name of the bitmap to decode.
-     * @param reqWidth The requested width of the resulting bitmap.
-     * @param reqHeight The requested height of the resulting bitmap.
-     * @return A bitmap sampled down from the original with the same aspect ratio and dimensions.
-     *         that are equal to or greater than the requested width and height.
-     */
-    @CalledByNative
-    private static Bitmap decodeDrawableResource(String name,
-                                                 int reqWidth,
-                                                 int reqHeight) {
-        Resources res = Resources.getSystem();
-        int resId = res.getIdentifier(name, null, null);
-        if (resId == 0) return null;
-
-        final BitmapFactory.Options options = new BitmapFactory.Options();
-        options.inJustDecodeBounds = true;
-        BitmapFactory.decodeResource(res, resId, options);
-
-        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
-        options.inJustDecodeBounds = false;
-        options.inPreferredConfig = Bitmap.Config.ARGB_8888;
-        return BitmapFactory.decodeResource(res, resId, options);
-    }
-
-    // http://developer.android.com/training/displaying-bitmaps/load-bitmap.html
-    private static int calculateInSampleSize(BitmapFactory.Options options,
-                                             int reqWidth,
-                                             int reqHeight) {
-        // Raw height and width of image
-        final int height = options.outHeight;
-        final int width = options.outWidth;
-        int inSampleSize = 1;
-
-        if (height > reqHeight || width > reqWidth) {
-
-            // Calculate ratios of height and width to requested height and width
-            final int heightRatio = Math.round((float) height / (float) reqHeight);
-            final int widthRatio = Math.round((float) width / (float) reqWidth);
-
-            // Choose the smallest ratio as inSampleSize value, this will guarantee
-            // a final image with both dimensions larger than or equal to the
-            // requested height and width.
-            inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
-        }
-
-        return inSampleSize;
-    }
-
-    /**
      * Provides a matching integer constant for the Bitmap.Config value passed.
      *
      * @param bitmapConfig The Bitmap Configuration value.
      * @return Matching integer constant for the Bitmap.Config value passed.
      */
     @CalledByNative
     private static int getBitmapFormatForConfig(Bitmap.Config bitmapConfig) {
         switch (bitmapConfig) {
             case ALPHA_8:
                 return BitmapFormat.ALPHA_8;
@@ skipping 22 matching lines @@
                 return Bitmap.Config.ARGB_4444;
             case BitmapFormat.RGB_565:
                 return Bitmap.Config.RGB_565;
             case BitmapFormat.ARGB_8888:
             default:
                 return Bitmap.Config.ARGB_8888;
         }
     }
 
 }