Photo Picker Dialog: Add caching for the decoded images.

chrome/android/java/src/org/chromium/chrome/browser/photo_picker/BitmapUtils.java

 // Copyright 2017 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.chrome.browser.photo_picker;
 
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 
 import java.io.FileDescriptor;
@@ skipping 89 matching lines @@
         int x = 0;
         int y = 0;
         int width = bitmap.getWidth();
         int height = bitmap.getHeight();
         if (width == size && height == size) return bitmap;
 
         if (width > size) x = (width - size) / 2;
         if (height > size) y = (height - size) / 2;
         return Bitmap.createBitmap(bitmap, x, y, size, size);
     }
+
+    /**
+     * Scales a |bitmap| to a certain size.
+     * @param bitmap The bitmap to scale.
+     * @param scaleMaxSize What to scale it to.
+     * @param filter True if the source should be filtered.
+     * @return The resulting scaled bitmap.
+     */
+    public static Bitmap scale(Bitmap bitmap, float scaleMaxSize, boolean filter) {
+        float ratio = Math.min((float) scaleMaxSize / bitmap.getWidth(),
+                (float) scaleMaxSize / bitmap.getHeight());
+        int height = Math.round(ratio * bitmap.getHeight());
+        int width = Math.round(ratio * bitmap.getWidth());
+
+        return Bitmap.createScaledBitmap(bitmap, width, height, filter);
+    }
 }