Implement the new Photo picker, part one.

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

Index: ui/android/java/src/org/chromium/ui/UiUtils.java
diff --git a/ui/android/java/src/org/chromium/ui/UiUtils.java b/ui/android/java/src/org/chromium/ui/UiUtils.java
index 61fa37f2cf3329ee49812dae8339a9d63282d62e..66e7a28019039ef8d71081ba25a3bac2cd127287 100644
--- a/ui/android/java/src/org/chromium/ui/UiUtils.java
+++ b/ui/android/java/src/org/chromium/ui/UiUtils.java
@@ -56,6 +56,9 @@ public class UiUtils {
     /** 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.
@@ -71,6 +74,25 @@ public class UiUtils {
     }
 
     /**
+     * A delegate interface for showing the photo picker.

[Michael van Ouwerkerk, 2017/03/14 15:57:27]

It does not just show, also dismiss. A more general description might be: "A
delegate interface for the photo picker."

[Finnur, 2017/03/15 13:25:07]

Yeah, sorry. I didn't follow your initial comment to the letter.

+     */
+    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 selection.
+         * @param allowMultiple Whether the dialog should allow multiple images to be selected.
+         */
+        void showPhotoPicker(
+                Context context, OnPhotoPickerListener listener, boolean allowMultiple);
+
+        /**
+         * Called when the photo picker dialog should be dismissed.
+         */
+        void dismissPhotoPicker();
+    }
+
+    /**
      * Allows setting a delegate to override the default software keyboard visibility detection.
      * @param delegate A {@link KeyboardShowingDelegate} instance.
      */
@@ -79,6 +101,14 @@ public class UiUtils {
     }
 
     /**
+     * Allows setting a delegate to override the default Android stock photo picker.
+     * @ param delegate A {@link PhotoPickerDelegate} instance.

[Michael van Ouwerkerk, 2017/03/14 15:57:27]

nit: no space after @

[Finnur, 2017/03/15 13:25:07]

Done.

+     */
+    public static void setPhotoPickerDelegate(PhotoPickerDelegate delegate) {
+        sPhotoPickerDelegate = delegate;
+    }
+
+    /**
      * Shows the software keyboard if necessary.
      * @param view The currently focused {@link View}, which would receive soft keyboard input.
      */
@@ -170,6 +200,20 @@ public class UiUtils {
         return locales;
     }
 
+    // PhotoPickerDelegate:
+
+    public static boolean showPhotoPicker(
+            Context context, OnPhotoPickerListener listener, boolean allowMultiple) {
+        if (sPhotoPickerDelegate == null) return false;
+        sPhotoPickerDelegate.showPhotoPicker(context, listener, allowMultiple);
+        return true;
+    }
+
+    public static void dismissPhotoPicker() {
+        if (sPhotoPickerDelegate == null) return;
+        sPhotoPickerDelegate.dismissPhotoPicker();
+    }
+
     /**
      * Inserts a {@link View} into a {@link ViewGroup} after directly before a given {@View}.
      * @param container The {@link View} to add newView to.