Implement the new Photo picker, part two.

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

Index: chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerBitmap.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerBitmap.java b/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerBitmap.java
new file mode 100644
index 0000000000000000000000000000000000000000..f73a1bbb0b22af530777bedd75111ec0880ecd43
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+++ b/chrome/android/java/src/org/chromium/chrome/browser/photo_picker/PickerBitmap.java
@@ -0,0 +1,82 @@
+// 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;
+
+/**
+ * A class to keep track of the meta data associated with a an image in the
+ * photo picker.
+ */
+public class PickerBitmap implements Comparable<PickerBitmap> {
+    // The possible types of tiles involved in the viewer.
+    public enum TileTypes { PICTURE, CAMERA, GALLERY }
+
+    // The file path to the bitmap to show.
+    private String mFilePath;
+
+    // When the bitmap was last modified on disk.
+    private long mLastModified;
+
+    // The type of tile involved.
+    private TileTypes mType;
+
+    /**
+     * The PickerBitmap constructor.
+     * @param filePath The file path to the bitmap to show.
+     * @param lastModified When the bitmap was last modified on disk.
+     * @param type The type of tile involved.
+     */
+    public PickerBitmap(String filePath, long lastModified, TileTypes type) {
+        mFilePath = filePath;
+        mLastModified = lastModified;
+        mType = type;
+    }
+
+    /**
+     * Accessor for the filepath.
+     * @return The file path for this PickerBitmap object.
+     */
+    public String getFilePath() {
+        return mFilePath;
+    }
+
+    /**
+     * Accessor for the tile type.
+     * @return The type of tile involved for this bitmap object.
+     */
+    public TileTypes type() {
+        return mType;
+    }
+
+    /**
+     * A comparison function for PickerBitmaps (results in a last-modified first sort).
+     * @param other The PickerBitmap to compare it to.
+     * @return 0, 1, or -1, depending on which is bigger.
+     */
+    @Override
+    public int compareTo(PickerBitmap other) {
+        if (mLastModified < other.mLastModified) {
+            return 1;
+        } else if (mLastModified > other.mLastModified) {
+            return -1;
+        }
+        return 0;
+    }
+
+    @Override
+    public final int hashCode() {
+        return (mFilePath + mLastModified).hashCode();
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other == this) {
+            return true;
+        }
+        if (other instanceof PickerBitmap) {
+            return compareTo((PickerBitmap) other) == 0;
+        }
+        return false;
+    }
+}