Implement the new Photo picker, part one.

ui/android/java/src/org/chromium/ui/UiUtils.java

 // Copyright 2013 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;
 
 import android.content.Context;
 import android.graphics.Bitmap;
 import android.graphics.Canvas;
 import android.graphics.Rect;
@@ skipping 38 matching lines @@
      */
     private UiUtils() {
     }
 
     /** The minimum size of the bottom margin below the app to detect a keyboard. */
     private static final float KEYBOARD_DETECT_BOTTOM_THRESHOLD_DP = 100;
 
     /** A delegate that allows disabling keyboard visibility detection. */
     private static KeyboardShowingDelegate sKeyboardShowingDelegate;
 
+    /** A delegate for the photo picker. */
+    private static PhotoPickerDelegate sPhotoPickerDelegate;
+
     /**
      * A delegate that can be implemented to override whether or not keyboard detection will be
      * used.
      */
     public interface KeyboardShowingDelegate {
         /**
          * Will be called to determine whether or not to detect if the keyboard is visible.
          * @param context A {@link Context} instance.
          * @param view    A {@link View}.
          * @return        Whether or not the keyboard check should be disabled.
          */
         boolean disableKeyboardCheck(Context context, View view);
     }
 
     /**
+     * A delegate interface for the photo picker.
+     */
+    public interface PhotoPickerDelegate {
+        /**
+         * Called to display the photo picker.
+         * @param context  The context to use.
+         * @param listener The listener that will be notified of the action the user took in the
+         *                 picker.
+         * @param allowMultiple Whether the dialog should allow multiple images to be selected.
+         */
+        void showPhotoPicker(Context context, PhotoPickerListener listener, boolean allowMultiple);
+
+        /**
+         * Called when the photo picker dialog should be dismissed.
+         */
+        void dismissPhotoPicker();
+    }
+
+    // PhotoPickerDelegate:
+
+    /**
+     * Called to display the photo picker.
+     * @param context  The context to use.
+     * @param listener The listener that will be notified of the action the user took in the
+     *                 picker.
+     * @param allowMultiple Whether the dialog should allow multiple images to be selected.
+     */
+    public static boolean showPhotoPicker(
+            Context context, PhotoPickerListener listener, boolean allowMultiple) {
+        if (sPhotoPickerDelegate == null) return false;
+        sPhotoPickerDelegate.showPhotoPicker(context, listener, allowMultiple);
+        return true;
+    }
+
+    /**
+     * Called when the photo picker dialog should be dismissed.
+     */
+    public static void dismissPhotoPicker() {
+        if (sPhotoPickerDelegate == null) return;
+        sPhotoPickerDelegate.dismissPhotoPicker();
+    }
+
+    // KeyboardShowingDelegate:
+
+    /**
      * Allows setting a delegate to override the default software keyboard visibility detection.
      * @param delegate A {@link KeyboardShowingDelegate} instance.
      */
     public static void setKeyboardShowingDelegate(KeyboardShowingDelegate delegate) {
         sKeyboardShowingDelegate = delegate;
     }
 
     /**
+     * Allows setting a delegate to override the default Android stock photo picker.
+     * @param delegate A {@link PhotoPickerDelegate} instance.
+     */
+    public static void setPhotoPickerDelegate(PhotoPickerDelegate delegate) {

[Theresa, 2017/03/16 16:26:17]

nit: move this above showPhotoPicker()

[Finnur, 2017/03/17 10:11:45]

Done.

+        sPhotoPickerDelegate = delegate;
+    }
+
+    /**
      * Shows the software keyboard if necessary.
      * @param view The currently focused {@link View}, which would receive soft keyboard input.
      */
     public static void showKeyboard(final View view) {
         final Handler handler = new Handler();
         final AtomicInteger attempt = new AtomicInteger();
         Runnable openRunnable = new Runnable() {
             @Override
             public void run() {
                 // Not passing InputMethodManager.SHOW_IMPLICIT as it does not trigger the
@@ skipping 232 matching lines @@
      * attached to the view hierarchy.
      *
      * @param view The view to be removed from the parent.
      */
     public static void removeViewFromParent(View view) {
         ViewGroup parent = (ViewGroup) view.getParent();
         if (parent == null) return;
         parent.removeView(view);
     }
 }