Photo Picker: Implement Zoom-in functionality.

The background for the Zoom icon is placeholder (haven't received
the 9patch image yet).

Animations between states will be included in a follow-up CL.

Bug: 1029056, 656015
Change-Id: Ic5657246ca21f7d6a1fcf26a42e2148d0771a05d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1936770
Commit-Queue: Finnur Thorarinsson <finnur@chromium.org>
Reviewed-by: Theresa  <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#719757}

chrome/android/java/res/drawable/photo_picker_zoom_background.xml

+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright 2019 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. -->
+<!-- TODO(finnur): Replace with real background -->
+
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item>
+        <shape>
+            <size android:width="42dp" android:height="42dp" />
+            <solid android:color="@color/modern_primary_color" />
+            <corners android:radius="42dp" />
+        </shape>
+    </item>
+</layer-list>

chrome/android/java/res/drawable/zoom_in.xml

+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright 2019 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. -->
+
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+
+    <path
+        android:fillColor="@color/default_icon_color"
+        android:pathData="M15.5 14h-0.79l-0.28-0.27C15.41 12.59 16 11.11 16 9.5 16 5.91 13.09 3 9.5 3S3 5.91 3 9.5 5.91 16 9.5 16c1.61 0 3.09-0.59 4.23-1.57l0.27 0.28 v0.79l5 4.99L20.49 19l-4.99-5zm-6 0C7.01 14 5 11.99 5 9.5S7.01 5 9.5 5 14 7.01 14 9.5 11.99 14 9.5 14z" />
+    <path
+        android:pathData="M0 0h24v24H0V0z" />
+    <path
+        android:fillColor="@color/default_icon_color"
+        android:pathData="M12 10h-2v2H9v-2H7V9h2V7h1v2h2v1z" />
+</vector>

chrome/android/java/res/drawable/zoom_out.xml

+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright 2019 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. -->
+
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+
+    <path
+        android:pathData="M0 0h24v24H0V0z" />
+    <path
+        android:fillColor="@color/default_icon_color"
+        android:pathData="M15.5 14h-0.79l-0.28-0.27C15.41 12.59 16 11.11 16 9.5 16 5.91 13.09 3 9.5 3S3 5.91 3 9.5 5.91 16 9.5 16c1.61 0 3.09-0.59 4.23-1.57l0.27 0.28 v0.79l5 4.99L20.49 19l-4.99-5zm-6 0C7.01 14 5 11.99 5 9.5S7.01 5 9.5 5 14 7.01 14 9.5 11.99 14 9.5 14zM7 9h5v1H7z" />
+</vector>

chrome/android/java/res/layout/photo_picker_bitmap_view.xml

@@ -12,7 +12,7 @@
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
-    android:layout_height="match_parent">
+    android:layout_height="wrap_content">
 
     <FrameLayout
         android:id="@+id/border"
@@ -96,7 +96,7 @@
 
         <TextView
             android:id="@+id/special_tile_label"
-            android:layout_width="match_parent"
+            android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_marginTop="@dimen/photo_picker_label_gap"
             android:gravity="center"

chrome/android/java/res/layout/photo_picker_dialog.xml

@@ -3,10 +3,9 @@
      Use of this source code is governed by a BSD-style license that can be
      found in the LICENSE file. -->
 
-<FrameLayout
+<org.chromium.ui.widget.OptimizedFrameLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:app="http://schemas.android.com/apk/res-auto"
-    xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:background="@color/default_bg_color_elev_0" >
@@ -17,6 +16,18 @@
         android:layout_height="match_parent"
         android:background="@color/modern_primary_color" />
 
+    <ImageView
+        android:id="@+id/zoom"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_gravity="bottom|end"
+        android:layout_marginEnd="20dp"
+        android:layout_marginBottom="20dp"
+        android:layout_centerHorizontal="true"
+        android:background="@drawable/photo_picker_zoom_background"
+        android:src="@drawable/zoom_in"
+        android:visibility="gone" />
+
     <RelativeLayout
         android:id="@+id/playback_container"
         android:layout_width="match_parent"
@@ -55,4 +66,4 @@
                 android:layout_height="wrap_content" />
         </LinearLayout>
     </RelativeLayout>
-</FrameLayout>
+</org.chromium.ui.widget.OptimizedFrameLayout>
\ No newline at end of file

chrome/android/java/res/values/dimens.xml

@@ -510,7 +510,6 @@
     <dimen name="contact_picker_icon_size">36dp</dimen>
 
     <!-- Photo Picker dimensions -->
-    <dimen name="photo_picker_selected_padding">12dp</dimen>
     <dimen name="photo_picker_label_gap">10dp</dimen>
     <dimen name="photo_picker_tile_min_size">100dp</dimen>
     <dimen name="photo_picker_tile_gap">4dp</dimen>

chrome/android/java/src/org/chromium/chrome/browser/ChromeFeatureList.java

@@ -307,6 +307,7 @@ public abstract class ChromeFeatureList {
     public static final String PER_METHOD_CAN_MAKE_PAYMENT_QUOTA =
             "WebPaymentsPerMethodCanMakePaymentQuota";
     public static final String PHOTO_PICKER_VIDEO_SUPPORT = "PhotoPickerVideoSupport";
+    public static final String PHOTO_PICKER_ZOOM = "PhotoPickerZoom";
     public static final String PREDICTIVE_PREFETCHING_ALLOWED_ON_ALL_CONNECTION_TYPES =
             "PredictivePrefetchingAllowedOnAllConnectionTypes";
     public static final String PRIORITIZE_BOOTSTRAP_TASKS = "PrioritizeBootstrapTasks";

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

@@ -24,17 +24,19 @@ class BitmapScalerTask extends AsyncTask<Bitmap> {
     private final int mSize;
     private final Bitmap mBitmap;
     private final String mVideoDuration;
+    private final float mRatio;
 
     /**
      * A BitmapScalerTask constructor.
      */
     public BitmapScalerTask(LruCache<String, PickerCategoryView.Thumbnail> cache, Bitmap bitmap,
-            String filePath, String videoDuration, int size) {
+            String filePath, String videoDuration, int size, float ratio) {
         mCache = cache;
         mFilePath = filePath;
         mSize = size;
         mBitmap = bitmap;
         mVideoDuration = videoDuration;
+        mRatio = ratio;
     }
 
     /**
@@ -66,6 +68,8 @@ class BitmapScalerTask extends AsyncTask<Bitmap> {
 
         List<Bitmap> bitmaps = new ArrayList<>(1);
         bitmaps.add(bitmap);
-        mCache.put(mFilePath, new PickerCategoryView.Thumbnail(bitmaps, mVideoDuration));
+        mCache.put(mFilePath,
+                new PickerCategoryView.Thumbnail(
+                        bitmaps, mVideoDuration, /*fullWidth=*/false, mRatio));
     }
 }

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

@@ -10,6 +10,7 @@ import android.graphics.Matrix;
 import android.media.ExifInterface;
 import android.media.MediaMetadataRetriever;
 import android.os.Build;
+import android.util.Pair;
 
 import org.chromium.base.metrics.RecordHistogram;
 
@@ -37,29 +38,44 @@ class BitmapUtils {
     private static final int EXIF_ORIENTATION_ACTION_BOUNDARY = 9;
 
     /**
-     * Takes a |bitmap| and returns a square thumbnail of |size|x|size| from the center of the
-     * bitmap specified, rotating it according to the Exif information, if needed (on Nougat and
-     * up only).
+     * Takes a |bitmap| and (if |!fullWidth|) returns a square thumbnail of |width|x|width| from the
+     * center of the bitmap specified, or (if |fullWidth|) an image that scaled to fit within
+     * |width|. The image is rotated according to the Exif information, if needed (on Nougat and up
+     * only).
      * @param bitmap The bitmap to adjust.
-     * @param size The desired size (width and height).
+     * @param width The desired width (and height if fullWidth is false).
+     * @param fullWidth Whether full screen width is in use. When true, the image returned is
+     *         |width| wide and whatever height scales to. When false, a rectangular |width|x|width|
+     *         image is returned.
      * @param descriptor The file descriptor to read the Exif information from.
      * @return The new bitmap thumbnail.
      */
-    private static Bitmap sizeBitmap(Bitmap bitmap, int size, FileDescriptor descriptor) {
+    private static Bitmap sizeBitmap(
+            Bitmap bitmap, int width, boolean fullWidth, FileDescriptor descriptor) {
         // TODO(finnur): Investigate options that require fewer bitmaps to be created.
-        bitmap = ensureMinSize(bitmap, size);
-        bitmap = rotateAndCropToSquare(bitmap, size, descriptor);
-        return bitmap;
+        if (!fullWidth) {
+            bitmap = ensureMinSize(bitmap, width);
+            bitmap = rotateAndCropToSquare(bitmap, width, descriptor);
+            return bitmap;
+        } else {
+            return rotateAndFitToMaxWidth(bitmap, width, descriptor);
+        }
     }
 
     /**
-     * Given a FileDescriptor, decodes the contents and returns a bitmap of
-     * dimensions |size|x|size|.
+     * Given a FileDescriptor, decodes the contents and returns a square thumbnail of
+     * |width|x|width| from the center of the bitmap specified, or (if |fullwidth|) an image that
+     * scaled to fit within |width|. The image is rotated according to the Exif information, if
+     * needed (on Nougat and up only).
      * @param descriptor The FileDescriptor for the file to read.
-     * @param size The width and height of the bitmap to return.
-     * @return The resulting bitmap.
+     * @param size The width of the bitmap to return.
+     * @param fullWidth Whether full screen width is in use. When true, the image returned is
+     *         |width| wide and whatever height scales to. When false, a rectangular |width|x|width|
+     *         image is returned.
+     * @return The resulting bitmap and its ratio.
      */
-    public static Bitmap decodeBitmapFromFileDescriptor(FileDescriptor descriptor, int size) {
+    public static Pair<Bitmap, Float> decodeBitmapFromFileDescriptor(
+            FileDescriptor descriptor, int size, boolean fullWidth) {
         BitmapFactory.Options options = new BitmapFactory.Options();
         options.inJustDecodeBounds = true;
         BitmapFactory.decodeFileDescriptor(descriptor, null, options);
@@ -69,31 +85,41 @@ class BitmapUtils {
 
         if (bitmap == null) return null;
 
-        return sizeBitmap(bitmap, size, descriptor);
+        return new Pair<Bitmap, Float>(sizeBitmap(bitmap, size, fullWidth, descriptor),
+                (float) bitmap.getHeight() / bitmap.getWidth());
     }
 
     /**
-     * Given a FileDescriptor, decodes the video and returns a bitmap of dimensions |size|x|size|.
+     * Given a FileDescriptor, decodes the video and returns a square thumbnail of |width|x|width|
+     * from the center of the bitmap specified, or (if |fullwidth|) an image that scaled to fit
+     * within |width|. The image is rotated according to the Exif information, if needed (on Nougat
+     * and up only).
      * @param retriever The MediaMetadataRetriever to use (must have source already set).
      * @param descriptor The FileDescriptor for the file to read.
-     * @param size The width and height of the bitmap to return.
+     * @param width The width of the bitmap to return.
      * @param frames The number of frames to extract.
+     * @param fullWidth Whether full screen width is in use. When true, the image returned is
+     *         |width| wide and whatever height scales to. When false, a rectangular |width|x|width|
+     *         image is returned.
      * @param intervalMs The interval between frames (in milliseconds).
      * @return A list of extracted frames.
      */
-    public static List<Bitmap> decodeVideoFromFileDescriptor(MediaMetadataRetriever retriever,
-            FileDescriptor descriptor, int size, int frames, long intervalMs) {
+    public static Pair<List<Bitmap>, Float> decodeVideoFromFileDescriptor(
+            MediaMetadataRetriever retriever, FileDescriptor descriptor, int width, int frames,
+            boolean fullWidth, long intervalMs) {
         List<Bitmap> bitmaps = new ArrayList<Bitmap>();
         Bitmap bitmap = null;
+        Float ratio = null;
         for (int frame = 0; frame < frames; ++frame) {
             bitmap = retriever.getFrameAtTime(frame * intervalMs * 1000);
             if (bitmap == null) continue;
+            if (ratio == null) ratio = (float) bitmap.getHeight() / bitmap.getWidth();
 
-            bitmap = sizeBitmap(bitmap, size, descriptor);
+            bitmap = sizeBitmap(bitmap, width, fullWidth, descriptor);
             bitmaps.add(bitmap);
         }
 
-        return bitmaps;
+        return new Pair<List<Bitmap>, Float>(bitmaps, ratio);
     }
 
     /**
@@ -158,14 +184,12 @@ class BitmapUtils {
     }
 
     /**
-     * Crops a |bitmap| to a certain square |size| and rotates it according to the Exif information,
-     * if needed (on Nougat and up only).
-     * @param bitmap The bitmap to crop.
-     * @param size The size desired (width and height).
-     * @return The resulting (square) bitmap.
+     * Returns the rotation matrix from the Exif information in the file descriptor (on Nougat and
+     * up only).
+     * @param descriptor The FileDescriptor containing the Exif information.
+     * @return The resulting rotation matrix (or null, if Android < N).
      */
-    private static Bitmap rotateAndCropToSquare(
-            Bitmap bitmap, int size, FileDescriptor descriptor) {
+    private static Matrix getRotationMatrix(FileDescriptor descriptor) {
         Matrix matrix = new Matrix();
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
             try {
@@ -215,7 +239,19 @@ class BitmapUtils {
             } catch (IOException e) {
             }
         }
+        return matrix;
+    }
 
+    /**
+     * Crops a |bitmap| to a certain square |size| and (on Nougat and up only) rotates it according
+     * to the Exif information, if needed.
+     * @param bitmap The bitmap to crop.
+     * @param size The size desired (width and height).
+     * @param descriptor The FileDescriptor containing the Exif information.
+     * @return The resulting (square) bitmap.
+     */
+    private static Bitmap rotateAndCropToSquare(
+            Bitmap bitmap, int size, FileDescriptor descriptor) {
         int x = 0;
         int y = 0;
         int width = bitmap.getWidth();
@@ -224,7 +260,25 @@ class BitmapUtils {
 
         if (width > size) x = (width - size) / 2;
         if (height > size) y = (height - size) / 2;
-        return Bitmap.createBitmap(bitmap, x, y, size, size, matrix, true);
+        return Bitmap.createBitmap(bitmap, x, y, size, size, getRotationMatrix(descriptor), true);
+    }
+
+    /**
+     * Rotate a bitmap according to its Exif information and make sure it fits to the maximum width.
+     * @param bitmap The input bitmap.
+     * @param maxWidth The maximum width available.
+     * @param descriptor The FileDescriptor containing the Exif information.
+     */
+    private static Bitmap rotateAndFitToMaxWidth(
+            Bitmap bitmap, int maxWidth, FileDescriptor descriptor) {
+        Bitmap rotated = bitmap;
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
+            rotated = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(),
+                    getRotationMatrix(descriptor), true);
+        }
+        float ratio = (float) maxWidth / rotated.getWidth();
+        int height = (int) (rotated.getHeight() * ratio);
+        return Bitmap.createScaledBitmap(rotated, maxWidth, height, true);
     }
 
     /**

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

@@ -26,7 +26,7 @@ import java.util.Locale;
 /**
  * A worker task to decode video and extract information from it off of the UI thread.
  */
-class DecodeVideoTask extends AsyncTask<Pair<List<Bitmap>, String>> {
+class DecodeVideoTask extends AsyncTask<List<Bitmap>> {
     /**
      * The possible error states while decoding.
      */
@@ -49,10 +49,11 @@ class DecodeVideoTask extends AsyncTask<Pair<List<Bitmap>, String>> {
          * @param uri The uri of the video decoded.
          * @param bitmaps An array of thumbnails extracted from the video.
          * @param duration The duration of the video.
+         * @param fullWidth Whether the image is using the full width of the screen.
          * @param decodingStatus Whether the decoding was successful.
          */
-        void videoDecodedCallback(
-                Uri uri, List<Bitmap> bitmaps, String duration, @DecodingResult int decodingStatus);
+        void videoDecodedCallback(Uri uri, List<Bitmap> bitmaps, String duration, boolean fullWidth,
+                @DecodingResult int decodingStatus, float ratio);
     }
 
     // The callback to use to communicate the results.
@@ -64,6 +65,9 @@ class DecodeVideoTask extends AsyncTask<Pair<List<Bitmap>, String>> {
     // The desired width and height (in pixels) of the returned thumbnail from the video.
     int mSize;
 
+    // Whether the image is taking up the full width of the screen.
+    boolean mFullWidth;
+
     // The number of frames to extract.
     int mFrames;
 
@@ -73,12 +77,15 @@ class DecodeVideoTask extends AsyncTask<Pair<List<Bitmap>, String>> {
     // The ContentResolver to use to retrieve image metadata from disk.
     private ContentResolver mContentResolver;
 
-    // A metadata retriever, used to decode the video, and extract a thumbnail frame.
-    private MediaMetadataRetriever mRetriever = new MediaMetadataRetriever();
-
     // Keeps track of errors during decoding.
     private @DecodingResult int mDecodingResult;
 
+    // The duration of the video.
+    private String mDuration;
+
+    // The ratio of the first frame of the video.
+    private float mRatio;
+
     /**
      * A DecodeVideoTask constructor.
      * @param callback The callback to use to communicate back the results.
@@ -86,15 +93,17 @@ class DecodeVideoTask extends AsyncTask<Pair<List<Bitmap>, String>> {
      * @param uri The URI of the video to decode.
      * @param size The desired width and height (in pixels) of the returned thumbnail from the
      *             video.
+     * @param fullWidth Whether this is a video thumbnail that takes up the full screen width.
      * @param frames The number of frames to extract.
      * @param intervalMs The interval between frames (in milliseconds).
      */
     public DecodeVideoTask(VideoDecodingCallback callback, ContentResolver contentResolver, Uri uri,
-            int size, int frames, long intervalMs) {
+            int size, boolean fullWidth, int frames, long intervalMs) {
         mCallback = callback;
         mContentResolver = contentResolver;
         mUri = uri;
         mSize = size;
+        mFullWidth = fullWidth;
         mFrames = frames;
         mIntervalMs = intervalMs;
     }
@@ -122,10 +131,10 @@ class DecodeVideoTask extends AsyncTask<Pair<List<Bitmap>, String>> {
 
     /**
      * Decodes a video and extracts metadata and a thumbnail. Called on a non-UI thread
-     * @return A pair of bitmap (video thumbnail) and the duration of the video.
+     * @return A list of bitmaps (video thumbnails).
      */
     @Override
-    protected Pair<List<Bitmap>, String> doInBackground() {
+    protected List<Bitmap> doInBackground() {
         assert !ThreadUtils.runningOnUiThread();
 
         if (isCancelled()) return null;
@@ -133,9 +142,10 @@ class DecodeVideoTask extends AsyncTask<Pair<List<Bitmap>, String>> {
         AssetFileDescriptor afd = null;
         try {
             afd = mContentResolver.openAssetFileDescriptor(mUri, "r");
-            mRetriever.setDataSource(afd.getFileDescriptor());
+            MediaMetadataRetriever retriever = new MediaMetadataRetriever();
+            retriever.setDataSource(afd.getFileDescriptor());
             String duration =
-                    mRetriever.extractMetadata(MediaMetadataRetriever.METADATA_KEY_DURATION);
+                    retriever.extractMetadata(MediaMetadataRetriever.METADATA_KEY_DURATION);
             if (duration != null) {
                 // Adjust to a shorter video, if the frame requests exceed the length of the video.
                 long durationMs = Long.parseLong(duration);
@@ -144,10 +154,11 @@ class DecodeVideoTask extends AsyncTask<Pair<List<Bitmap>, String>> {
                 }
                 duration = formatDuration(duration);
             }
-            List<Bitmap> bitmaps = BitmapUtils.decodeVideoFromFileDescriptor(
-                    mRetriever, afd.getFileDescriptor(), mSize, mFrames, mIntervalMs);
-
-            return new Pair<List<Bitmap>, String>(bitmaps, duration);
+            Pair<List<Bitmap>, Float> bitmaps = BitmapUtils.decodeVideoFromFileDescriptor(
+                    retriever, afd.getFileDescriptor(), mSize, mFrames, mFullWidth, mIntervalMs);
+            mDuration = duration;
+            mRatio = bitmaps.second;
+            return bitmaps.first;
         } catch (FileNotFoundException exception) {
             mDecodingResult = DecodingResult.FILE_ERROR;
             return null;
@@ -170,16 +181,17 @@ class DecodeVideoTask extends AsyncTask<Pair<List<Bitmap>, String>> {
      * @param results A pair of bitmap (video thumbnail) and the duration of the video.
      */
     @Override
-    protected void onPostExecute(Pair<List<Bitmap>, String> results) {
+    protected void onPostExecute(List<Bitmap> results) {
         if (isCancelled()) {
             return;
         }
 
         if (results == null) {
-            mCallback.videoDecodedCallback(mUri, null, "", mDecodingResult);
+            mCallback.videoDecodedCallback(mUri, null, "", mFullWidth, mDecodingResult, 1.0f);
             return;
         }
 
-        mCallback.videoDecodedCallback(mUri, results.first, results.second, mDecodingResult);
+        mCallback.videoDecodedCallback(
+                mUri, results, mDuration, mFullWidth, mDecodingResult, mRatio);
     }
 }

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

@@ -12,6 +12,7 @@ import android.os.IBinder;
 import android.os.ParcelFileDescriptor;
 import android.os.RemoteException;
 import android.os.SystemClock;
+import android.util.Pair;
 
 import org.chromium.base.CommandLine;
 import org.chromium.base.Log;
@@ -36,7 +37,9 @@ public class DecoderService extends Service {
     static final String KEY_FILE_DESCRIPTOR = "file_descriptor";
     static final String KEY_FILE_PATH = "file_path";
     static final String KEY_IMAGE_BITMAP = "image_bitmap";
-    static final String KEY_SIZE = "size";
+    static final String KEY_WIDTH = "width";
+    static final String KEY_RATIO = "ratio";
+    static final String KEY_FULL_WIDTH = "full_width";
     static final String KEY_SUCCESS = "success";
     static final String KEY_DECODE_TIME = "decode_time";
 
@@ -79,11 +82,13 @@ public class DecoderService extends Service {
         public void decodeImage(Bundle payload, IDecoderServiceCallback callback) {
             Bundle bundle = null;
             String filePath = "";
-            int size = 0;
+            int width = 0;
+            boolean fullWidth = false;
             try {
                 filePath = payload.getString(KEY_FILE_PATH);
                 ParcelFileDescriptor pfd = payload.getParcelable(KEY_FILE_DESCRIPTOR);
-                size = payload.getInt(KEY_SIZE);
+                width = payload.getInt(KEY_WIDTH);
+                fullWidth = payload.getBoolean(KEY_FULL_WIDTH);
 
                 // Setup a minimum viable response to parent process. Will be fleshed out
                 // further below.
@@ -92,7 +97,7 @@ public class DecoderService extends Service {
                 bundle.putBoolean(KEY_SUCCESS, false);
 
                 if (!mNativeLibraryAndSandboxInitialized) {
-                    Log.e(TAG, "Decode failed %s (size: %d): no sandbox", filePath, size);
+                    Log.e(TAG, "Decode failed %s (width: %d): no sandbox", filePath, width);
                     sendReply(callback, bundle); // Sends SUCCESS == false;
                     return;
                 }
@@ -100,17 +105,19 @@ public class DecoderService extends Service {
                 FileDescriptor fd = pfd.getFileDescriptor();
 
                 long begin = SystemClock.elapsedRealtime();
-                Bitmap bitmap = BitmapUtils.decodeBitmapFromFileDescriptor(fd, size);
+                Pair<Bitmap, Float> decodedBitmap =
+                        BitmapUtils.decodeBitmapFromFileDescriptor(fd, width, fullWidth);
                 long decodeTime = SystemClock.elapsedRealtime() - begin;
 
                 try {
                     pfd.close();
                 } catch (IOException e) {
-                    Log.e(TAG, "Closing failed " + filePath + " (size: " + size + ") " + e);
+                    Log.e(TAG, "Closing failed " + filePath + " (width: " + width + ") " + e);
                 }
 
+                Bitmap bitmap = decodedBitmap.first;
                 if (bitmap == null) {
-                    Log.e(TAG, "Decode failed " + filePath + " (size: " + size + ")");
+                    Log.e(TAG, "Decode failed " + filePath + " (width: " + width + ")");
                     sendReply(callback, bundle); // Sends SUCCESS == false;
                     return;
                 }
@@ -121,8 +128,10 @@ public class DecoderService extends Service {
                 // descriptor. In the receiving process it will just leave the bitmap on
                 // ashmem since it's immutable and carry on.
                 bundle.putParcelable(KEY_IMAGE_BITMAP, bitmap);
+                bundle.putFloat(KEY_RATIO, decodedBitmap.second);
                 bundle.putBoolean(KEY_SUCCESS, true);
                 bundle.putLong(KEY_DECODE_TIME, decodeTime);
+                bundle.putBoolean(KEY_FULL_WIDTH, payload.getBoolean(KEY_FULL_WIDTH));
                 sendReply(callback, bundle);
                 bitmap.recycle();
             } catch (Exception e) {
@@ -130,7 +139,7 @@ public class DecoderService extends Service {
                 // decoding a photo, it is better UX to eat the exception instead of showing
                 // a crash dialog and discarding other requests that have already been sent.
                 Log.e(TAG,
-                        "Unexpected error during decoding " + filePath + " (size: " + size + ") "
+                        "Unexpected error during decoding " + filePath + " (width: " + width + ") "
                                 + e);
 
                 if (bundle != null) sendReply(callback, bundle);

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

@@ -43,8 +43,8 @@ public class PickerBitmapViewHolder
     // DecoderServiceHost.ImageDecodedCallback
 
     @Override
-    public void imagesDecodedCallback(
-            String filePath, boolean isVideo, List<Bitmap> bitmaps, String videoDuration) {
+    public void imagesDecodedCallback(String filePath, boolean isVideo, boolean fullWidth,
+            List<Bitmap> bitmaps, String videoDuration, float ratio) {
         if (bitmaps == null || bitmaps.size() == 0) return;
 
         if (!isVideo) {
@@ -52,20 +52,27 @@ public class PickerBitmapViewHolder
             if (bitmap == null || bitmap.getWidth() == 0 || bitmap.getHeight() == 0) return;
         }
 
-        PickerCategoryView.Thumbnail cachedThumbnail =
-                mCategoryView.getHighResThumbnails().get(filePath);
+        PickerCategoryView.Thumbnail cachedThumbnail = fullWidth
+                ? mCategoryView.getFullScreenBitmaps().get(filePath)
+                : mCategoryView.getHighResThumbnails().get(filePath);
         if (cachedThumbnail == null
                 || (cachedThumbnail.bitmaps != null
                         && cachedThumbnail.bitmaps.size() < bitmaps.size())) {
-            mCategoryView.getHighResThumbnails().put(
-                    filePath, new PickerCategoryView.Thumbnail(bitmaps, videoDuration));
+            if (fullWidth) {
+                mCategoryView.getFullScreenBitmaps().put(filePath,
+                        new PickerCategoryView.Thumbnail(bitmaps, videoDuration, fullWidth, ratio));
+            } else {
+                mCategoryView.getHighResThumbnails().put(filePath,
+                        new PickerCategoryView.Thumbnail(bitmaps, videoDuration, fullWidth, ratio));
+            }
         }
 
         if (mCategoryView.getLowResThumbnails().get(filePath) == null) {
             Resources resources = mItemView.getContext().getResources();
             new BitmapScalerTask(mCategoryView.getLowResThumbnails(), bitmaps.get(0), filePath,
                     videoDuration,
-                    resources.getDimensionPixelSize(R.dimen.photo_picker_grainy_thumbnail_size))
+                    resources.getDimensionPixelSize(R.dimen.photo_picker_grainy_thumbnail_size),
+                    ratio)
                     .executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
         }
 
@@ -73,7 +80,7 @@ public class PickerBitmapViewHolder
             return;
         }
 
-        if (mItemView.setThumbnailBitmap(bitmaps, videoDuration)) {
+        if (mItemView.setThumbnailBitmap(bitmaps, videoDuration, ratio)) {
             mItemView.fadeInThumbnail();
         }
     }
@@ -93,37 +100,48 @@ public class PickerBitmapViewHolder
 
         if (mBitmapDetails.type() == PickerBitmap.TileTypes.CAMERA
                 || mBitmapDetails.type() == PickerBitmap.TileTypes.GALLERY) {
-            mItemView.initialize(mBitmapDetails, null, null, false);
+            mItemView.initialize(mBitmapDetails, null, null, false, -1);
             return PickerAdapter.DecodeActions.NO_ACTION;
         }
 
         String filePath = mBitmapDetails.getUri().getPath();
-        PickerCategoryView.Thumbnail original = mCategoryView.getHighResThumbnails().get(filePath);
+        PickerCategoryView.Thumbnail original = mCategoryView.isInMagnifyingMode()
+                ? mCategoryView.getFullScreenBitmaps().get(filePath)
+                : mCategoryView.getHighResThumbnails().get(filePath);
         if (original != null) {
-            mItemView.initialize(mBitmapDetails, original.bitmaps, original.videoDuration, false);
+            mItemView.initialize(mBitmapDetails, original.bitmaps, original.videoDuration, false,
+                    original.ratio);
             return PickerAdapter.DecodeActions.FROM_CACHE;
         }
 
-        int size = mCategoryView.getImageSize();
-        PickerCategoryView.Thumbnail payload = mCategoryView.getLowResThumbnails().get(filePath);
+        int width = mCategoryView.getImageWidth();
+        PickerCategoryView.Thumbnail payload = null;
+        if (mCategoryView.isInMagnifyingMode()) {
+            payload = mCategoryView.getHighResThumbnails().get(filePath);
+        }
+        if (payload == null) {
+            payload = mCategoryView.getLowResThumbnails().get(filePath);
+        }
+
         if (payload != null) {
             Bitmap placeholder = payload.bitmaps.get(0);
             // For performance stats see http://crbug.com/719919.
             long begin = SystemClock.elapsedRealtime();
-            placeholder = BitmapUtils.scale(placeholder, size, false);
+            placeholder = BitmapUtils.scale(placeholder, width, false);
             long scaleTime = SystemClock.elapsedRealtime() - begin;
             RecordHistogram.recordTimesHistogram(
                     "Android.PhotoPicker.UpscaleLowResBitmap", scaleTime);
             List<Bitmap> bitmaps = new ArrayList<>(1);
             bitmaps.add(placeholder);
 
-            mItemView.initialize(mBitmapDetails, bitmaps, payload.videoDuration, true);
+            mItemView.initialize(
+                    mBitmapDetails, bitmaps, payload.videoDuration, true, payload.ratio);
         } else {
-            mItemView.initialize(mBitmapDetails, null, null, true);
+            mItemView.initialize(mBitmapDetails, null, null, true, -1);
         }
 
-        mCategoryView.getDecoderServiceHost().decodeImage(
-                mBitmapDetails.getUri(), mBitmapDetails.type(), size, this);
+        mCategoryView.getDecoderServiceHost().decodeImage(mBitmapDetails.getUri(),
+                mBitmapDetails.type(), width, mCategoryView.isInMagnifyingMode(), this);
         return PickerAdapter.DecodeActions.DECODE;
     }
 
@@ -134,8 +152,9 @@ public class PickerBitmapViewHolder
     public String getFilePath() {
         if (mBitmapDetails == null
                 || (mBitmapDetails.type() != PickerBitmap.TileTypes.PICTURE
-                        && mBitmapDetails.type() != PickerBitmap.TileTypes.VIDEO))
+                        && mBitmapDetails.type() != PickerBitmap.TileTypes.VIDEO)) {
             return null;
+        }
         return mBitmapDetails.getUri().getPath();
     }
 }

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

@@ -22,6 +22,7 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.widget.Button;
 import android.widget.FrameLayout;
+import android.widget.ImageView;
 import android.widget.MediaController;
 import android.widget.RelativeLayout;
 import android.widget.VideoView;
@@ -33,6 +34,7 @@ import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.base.task.AsyncTask;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ChromeActivity;
+import org.chromium.chrome.browser.ChromeFeatureList;
 import org.chromium.chrome.browser.util.ConversionUtils;
 import org.chromium.chrome.browser.widget.selection.SelectableListLayout;
 import org.chromium.chrome.browser.widget.selection.SelectionDelegate;
@@ -65,11 +67,19 @@ public class PickerCategoryView extends RelativeLayout
      */
     public static class Thumbnail {
         public List<Bitmap> bitmaps;
+        public Boolean fullWidth;
         public String videoDuration;
 
-        Thumbnail(List<Bitmap> bitmaps, String videoDuration) {
+        // The calculated ratio of the originals for the bitmaps above, were they to be shown
+        // un-cropped. NOTE: The |bitmaps| above may already have been cropped and as such might
+        // have a different ratio.
+        public float ratio;
+
+        Thumbnail(List<Bitmap> bitmaps, String videoDuration, Boolean fullWidth, float ratio) {
             this.bitmaps = bitmaps;
             this.videoDuration = videoDuration;
+            this.fullWidth = fullWidth;
+            this.ratio = ratio;
         }
     }
 
@@ -117,12 +127,24 @@ public class PickerCategoryView extends RelativeLayout
     // A high-resolution cache for thumbnails, lazily created.
     private DiscardableReference<LruCache<String, Thumbnail>> mHighResThumbnails;
 
+    // A cache for full-screen versions of images, lazily created.
+    private DiscardableReference<LruCache<String, Thumbnail>> mFullScreenBitmaps;
+
     // The size of the low-res cache.
     private int mCacheSizeLarge;
 
     // The size of the high-res cache.
     private int mCacheSizeSmall;
 
+    // The size of the full-screen cache.
+    private int mCacheSizeFullScreen;
+
+    // Whether we are in magnifying mode (one image per column).
+    private boolean mMagnifyingMode;
+
+    // Whether we are in the middle of animating between magnifying modes.
+    private boolean mZoomSwitchingInEffect;
+
     /**
      * The number of columns to show. Note: mColumns and mPadding (see below) should both be even
      * numbers or both odd, not a mix (the column padding will not be of uniform thickness if they
@@ -133,8 +155,14 @@ public class PickerCategoryView extends RelativeLayout
     // The padding between columns. See also comment for mColumns.
     private int mPadding;
 
-    // The size of the bitmaps (equal length for width and height).
-    private int mImageSize;
+    // The width of the bitmaps.
+    private int mImageWidth;
+
+    // The height of the bitmaps.
+    private int mImageHeight;
+
+    // The height of the special tiles.
+    private int mSpecialTileHeight;
 
     // A worker task for asynchronously enumerating files off the main thread.
     private FileEnumWorkerTask mWorkerTask;
@@ -191,6 +219,12 @@ public class PickerCategoryView extends RelativeLayout
         doneButton.setOnClickListener(this);
         mVideoView = findViewById(R.id.video_player);
 
+        if (ChromeFeatureList.isEnabled(ChromeFeatureList.PHOTO_PICKER_ZOOM)) {
+            ImageView zoom = findViewById(R.id.zoom);
+            zoom.setVisibility(View.VISIBLE);
+            zoom.setOnClickListener(this);
+        }
+
         calculateGridMetrics();
 
         mLayoutManager = new GridLayoutManager(mActivity, mColumns);
@@ -201,7 +235,13 @@ public class PickerCategoryView extends RelativeLayout
         mRecyclerView.setRecyclerListener(this);
 
         final long maxMemory = ConversionUtils.bytesToKilobytes(Runtime.getRuntime().maxMemory());
-        mCacheSizeLarge = (int) (maxMemory / 2); // 1/2 of the available memory.
+        if (ChromeFeatureList.isEnabled(ChromeFeatureList.PHOTO_PICKER_ZOOM)) {
+            mCacheSizeFullScreen = (int) (maxMemory / 4); // 1/4 of the available memory.
+            mCacheSizeLarge = (int) (maxMemory / 4); // 1/4 of the available memory.
+        } else {
+            mCacheSizeFullScreen = 0;
+            mCacheSizeLarge = (int) (maxMemory / 2); // 1/2 of the available memory.
+        }
         mCacheSizeSmall = (int) (maxMemory / 8); // 1/8th of the available memory.
     }
 
@@ -219,7 +259,10 @@ public class PickerCategoryView extends RelativeLayout
         // enumerated (when mPickerBitmaps is null, causing: https://crbug.com/947657). There's no
         // need to call notifyDataSetChanged in that case because it will be called once the photo
         // list becomes ready.
-        if (mPickerBitmaps != null) mPickerAdapter.notifyDataSetChanged();
+        if (mPickerBitmaps != null) {
+            mPickerAdapter.notifyDataSetChanged();
+            mRecyclerView.requestLayout();
+        }
     }
 
     /**
@@ -347,6 +390,8 @@ public class PickerCategoryView extends RelativeLayout
         int id = view.getId();
         if (id == R.id.done) {
             notifyPhotosSelected();
+        } else if (id == R.id.zoom) {
+            flipZoomMode();
         } else if (id == R.id.close) {
             stopVideo();
         } else {
@@ -364,10 +409,39 @@ public class PickerCategoryView extends RelativeLayout
         }
     }
 
+    private void flipZoomMode() {
+        mMagnifyingMode = !mMagnifyingMode;
+
+        ImageView zoom = findViewById(R.id.zoom);
+        if (mMagnifyingMode) {
+            zoom.setImageResource(R.drawable.zoom_out);
+        } else {
+            zoom.setImageResource(R.drawable.zoom_in);
+        }
+
+        calculateGridMetrics();
+
+        mLayoutManager.setSpanCount(mColumns);
+        mPickerAdapter.notifyDataSetChanged();
+        mRecyclerView.requestLayout();
+    }
+
     // Simple accessors:
 
-    public int getImageSize() {
-        return mImageSize;
+    public int getImageWidth() {
+        return mImageWidth;
+    }
+
+    public int getImageHeight() {
+        return mImageHeight;
+    }
+
+    public int getSpecialTileHeight() {
+        return mSpecialTileHeight;
+    }
+
+    public boolean isInMagnifyingMode() {
+        return mMagnifyingMode;
     }
 
     public SelectionDelegate<PickerBitmap> getSelectionDelegate() {
@@ -398,6 +472,14 @@ public class PickerCategoryView extends RelativeLayout
         return mHighResThumbnails.get();
     }
 
+    public LruCache<String, Thumbnail> getFullScreenBitmaps() {
+        if (mFullScreenBitmaps == null || mFullScreenBitmaps.get() == null) {
+            mFullScreenBitmaps = mActivity.getReferencePool().put(
+                    new LruCache<String, Thumbnail>(mCacheSizeFullScreen));
+        }
+        return mFullScreenBitmaps.get();
+    }
+
     public boolean isMultiSelectAllowed() {
         return mMultiSelectionAllowed;
     }
@@ -426,12 +508,18 @@ public class PickerCategoryView extends RelativeLayout
         int width = displayMetrics.widthPixels;
         int minSize =
                 mActivity.getResources().getDimensionPixelSize(R.dimen.photo_picker_tile_min_size);
-        mPadding = mActivity.getResources().getDimensionPixelSize(R.dimen.photo_picker_tile_gap);
-        mColumns = Math.max(1, (width - mPadding) / (minSize + mPadding));
-        mImageSize = (width - mPadding * (mColumns + 1)) / (mColumns);
+        mPadding = mMagnifyingMode
+                ? 0
+                : mActivity.getResources().getDimensionPixelSize(R.dimen.photo_picker_tile_gap);
+        mColumns = mMagnifyingMode ? 1 : Math.max(1, (width - mPadding) / (minSize + mPadding));
+        mImageWidth = (width - mPadding * (mColumns + 1)) / (mColumns);
+        mImageHeight = mMagnifyingMode
+                ? displayMetrics.heightPixels - findViewById(R.id.action_bar_bg).getHeight()
+                : mImageWidth;
+        if (!mMagnifyingMode) mSpecialTileHeight = mImageWidth;
 
         // Make sure columns and padding are either both even or both odd.
-        if (((mColumns % 2) == 0) != ((mPadding % 2) == 0)) {
+        if (!mMagnifyingMode && ((mColumns % 2) == 0) != ((mPadding % 2) == 0)) {
             mPadding++;
         }
     }
@@ -495,6 +583,11 @@ public class PickerCategoryView extends RelativeLayout
         @Override
         public void getItemOffsets(
                 Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
+            if (mMagnifyingMode) {
+                outRect.set(0, 0, 0, mSpacing);
+                return;
+            }
+
             int left = 0, right = 0, top = 0, bottom = 0;
             int position = parent.getChildAdapterPosition(view);
 

chrome/android/javatests/src/org/chromium/chrome/browser/photo_picker/DecoderServiceHostTest.java

@@ -18,7 +18,7 @@ import org.junit.runner.RunWith;
 
 import org.chromium.base.test.util.CallbackHelper;
 import org.chromium.base.test.util.CommandLineFlags;
-import org.chromium.base.test.util.DisableIf;
+import org.chromium.base.test.util.MinAndroidSdkLevel;
 import org.chromium.base.test.util.UrlUtils;
 import org.chromium.chrome.browser.ChromeActivity;
 import org.chromium.chrome.browser.ChromeSwitches;
@@ -33,6 +33,7 @@ import java.util.concurrent.TimeUnit;
  * Tests for the DecoderServiceHost.
  */
 @RunWith(ChromeJUnit4ClassRunner.class)
+@MinAndroidSdkLevel(Build.VERSION_CODES.N)
 @CommandLineFlags.Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE})
 public class DecoderServiceHostTest implements DecoderServiceHost.ServiceReadyCallback,
                                                DecoderServiceHost.ImagesDecodedCallback {
@@ -53,8 +54,10 @@ public class DecoderServiceHostTest implements DecoderServiceHost.ServiceReadyCa
 
     private String mLastDecodedPath;
     private boolean mLastIsVideo;
+    private Bitmap mLastInitialFrame;
     private int mLastFrameCount;
     private String mLastVideoDuration;
+    private float mLastRatio;
 
     @Before
     public void setUp() throws Exception {
@@ -74,12 +77,14 @@ public class DecoderServiceHostTest implements DecoderServiceHost.ServiceReadyCa
     // DecoderServiceHost.ImagesDecodedCallback:
 
     @Override
-    public void imagesDecodedCallback(
-            String filePath, boolean isVideo, List<Bitmap> bitmaps, String videoDuration) {
+    public void imagesDecodedCallback(String filePath, boolean isVideo, boolean isZoomedIn,
+            List<Bitmap> bitmaps, String videoDuration, float ratio) {
         mLastDecodedPath = filePath;
         mLastIsVideo = isVideo;
         mLastFrameCount = bitmaps != null ? bitmaps.size() : -1;
+        mLastInitialFrame = bitmaps != null ? bitmaps.get(0) : null;
         mLastVideoDuration = videoDuration;
+        mLastRatio = ratio;
 
         onDecodedCallback.notifyCalled();
     }
@@ -96,7 +101,6 @@ public class DecoderServiceHostTest implements DecoderServiceHost.ServiceReadyCa
     }
 
     @Test
-    @DisableIf.Build(sdk_is_less_than = Build.VERSION_CODES.N)
     @LargeTest
     public void testDecodingOrder() throws Throwable {
         DecoderServiceHost host = new DecoderServiceHost(this, mContext);
@@ -111,9 +115,12 @@ public class DecoderServiceHostTest implements DecoderServiceHost.ServiceReadyCa
         File file2 = new File(UrlUtils.getIsolatedTestFilePath(filePath + fileName2));
         File file3 = new File(UrlUtils.getIsolatedTestFilePath(filePath + fileName3));
 
-        host.decodeImage(Uri.fromFile(file1), PickerBitmap.TileTypes.VIDEO, 10, this);
-        host.decodeImage(Uri.fromFile(file2), PickerBitmap.TileTypes.VIDEO, 10, this);
-        host.decodeImage(Uri.fromFile(file3), PickerBitmap.TileTypes.PICTURE, 10, this);
+        host.decodeImage(
+                Uri.fromFile(file1), PickerBitmap.TileTypes.VIDEO, 10, /*fullWidth=*/false, this);
+        host.decodeImage(
+                Uri.fromFile(file2), PickerBitmap.TileTypes.VIDEO, 10, /*fullWidth=*/false, this);
+        host.decodeImage(
+                Uri.fromFile(file3), PickerBitmap.TileTypes.PICTURE, 10, /*fullWidth=*/false, this);
 
         // First decoding result should be first frame only of video 1.
         waitForThumbnailDecode();
@@ -153,4 +160,84 @@ public class DecoderServiceHostTest implements DecoderServiceHost.ServiceReadyCa
 
         host.unbind(mContext);
     }
+
+    @Test
+    @LargeTest
+    public void testDecodingSizes() throws Throwable {
+        DecoderServiceHost host = new DecoderServiceHost(this, mContext);
+        host.bind(mContext);
+        waitForDecoder();
+
+        String fileName1 = "noogler.mp4"; // 1920 x 1080 video.
+        String fileName2 = "blue100x100.jpg";
+        String filePath = "chrome/test/data/android/photo_picker/";
+        File file1 = new File(UrlUtils.getIsolatedTestFilePath(filePath + fileName1));
+        File file2 = new File(UrlUtils.getIsolatedTestFilePath(filePath + fileName2));
+
+        // Thumbnail photo. 100 x 100 -> 10 x 10.
+        host.decodeImage(
+                Uri.fromFile(file2), PickerBitmap.TileTypes.PICTURE, 10, /*fullWidth=*/false, this);
+        waitForThumbnailDecode();
+        Assert.assertTrue(mLastDecodedPath.contains(fileName2));
+        Assert.assertEquals(false, mLastIsVideo);
+        Assert.assertEquals(null, mLastVideoDuration);
+        Assert.assertEquals(1, mLastFrameCount);
+        Assert.assertEquals(1.0f, mLastRatio, 0.1f);
+        Assert.assertEquals(10, mLastInitialFrame.getWidth());
+        Assert.assertEquals(10, mLastInitialFrame.getHeight());
+
+        // Full-width photo. 100 x 100 -> 200 x 200.
+        host.decodeImage(
+                Uri.fromFile(file2), PickerBitmap.TileTypes.PICTURE, 200, /*fullWidth=*/true, this);
+        waitForThumbnailDecode();
+        Assert.assertTrue(mLastDecodedPath.contains(fileName2));
+        Assert.assertEquals(false, mLastIsVideo);
+        Assert.assertEquals(null, mLastVideoDuration);
+        Assert.assertEquals(1, mLastFrameCount);
+        Assert.assertEquals(1.0f, mLastRatio, 0.1f);
+        Assert.assertEquals(200, mLastInitialFrame.getWidth());
+        Assert.assertEquals(200, mLastInitialFrame.getHeight());
+
+        // Thumbnail video. 1920 x 1080 -> 10 x 10.
+        host.decodeImage(
+                Uri.fromFile(file1), PickerBitmap.TileTypes.VIDEO, 10, /*fullWidth=*/false, this);
+        waitForThumbnailDecode(); // Initial frame.
+        Assert.assertTrue(mLastDecodedPath.contains(fileName1));
+        Assert.assertEquals(true, mLastIsVideo);
+        Assert.assertEquals("00:00", mLastVideoDuration);
+        Assert.assertEquals(1, mLastFrameCount);
+        Assert.assertEquals(0.5625f, mLastRatio, 0.0001f);
+        Assert.assertEquals(10, mLastInitialFrame.getWidth());
+        Assert.assertEquals(10, mLastInitialFrame.getHeight());
+        waitForThumbnailDecode(); // Rest of frames.
+        Assert.assertTrue(mLastDecodedPath.contains(fileName1));
+        Assert.assertEquals(true, mLastIsVideo);
+        Assert.assertEquals("00:00", mLastVideoDuration);
+        Assert.assertEquals(10, mLastFrameCount);
+        Assert.assertEquals(0.5625f, mLastRatio, 0.0001f);
+        Assert.assertEquals(10, mLastInitialFrame.getWidth());
+        Assert.assertEquals(10, mLastInitialFrame.getHeight());
+
+        // Full-width video. 1920 x 1080 -> 2000 x 1125.
+        host.decodeImage(
+                Uri.fromFile(file1), PickerBitmap.TileTypes.VIDEO, 2000, /*fullWidth=*/true, this);
+        waitForThumbnailDecode(); // Initial frame.
+        Assert.assertTrue(mLastDecodedPath.contains(fileName1));
+        Assert.assertEquals(true, mLastIsVideo);
+        Assert.assertEquals("00:00", mLastVideoDuration);
+        Assert.assertEquals(1, mLastFrameCount);
+        Assert.assertEquals(0.5625f, mLastRatio, 0.0001f);
+        Assert.assertEquals(2000, mLastInitialFrame.getWidth());
+        Assert.assertEquals(1125, mLastInitialFrame.getHeight());
+        waitForThumbnailDecode(); // Rest of frames.
+        Assert.assertTrue(mLastDecodedPath.contains(fileName1));
+        Assert.assertEquals(true, mLastIsVideo);
+        Assert.assertEquals("00:00", mLastVideoDuration);
+        Assert.assertEquals(10, mLastFrameCount);
+        Assert.assertEquals(0.5625f, mLastRatio, 0.0001f);
+        Assert.assertEquals(2000, mLastInitialFrame.getWidth());
+        Assert.assertEquals(1125, mLastInitialFrame.getHeight());
+
+        host.unbind(mContext);
+    }
 }

chrome/android/javatests/src/org/chromium/chrome/browser/photo_picker/DecoderServiceTest.java

@@ -102,7 +102,7 @@ public class DecoderServiceTest {
         });
     }
 
-    private void decode(String filePath, FileDescriptor fd, int size,
+    private void decode(String filePath, FileDescriptor fd, int width,
             final DecoderServiceCallback callback) throws Exception {
         Bundle bundle = new Bundle();
         bundle.putString(DecoderService.KEY_FILE_PATH, filePath);
@@ -112,7 +112,7 @@ public class DecoderServiceTest {
             Assert.assertTrue(pfd != null);
         }
         bundle.putParcelable(DecoderService.KEY_FILE_DESCRIPTOR, pfd);
-        bundle.putInt(DecoderService.KEY_SIZE, size);
+        bundle.putInt(DecoderService.KEY_WIDTH, width);
 
         mIRemoteService.decodeImage(bundle, callback);
         CriteriaHelper.pollUiThread(new Criteria() {

chrome/android/javatests/src/org/chromium/chrome/browser/photo_picker/PhotoPickerDialogTest.java

@@ -21,7 +21,7 @@ import org.junit.runner.RunWith;
 
 import org.chromium.base.test.util.CallbackHelper;
 import org.chromium.base.test.util.CommandLineFlags;
-import org.chromium.base.test.util.DisableIf;
+import org.chromium.base.test.util.MinAndroidSdkLevel;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ChromeActivity;
 import org.chromium.chrome.browser.ChromeSwitches;
@@ -44,6 +44,7 @@ import java.util.concurrent.TimeUnit;
  * Tests for the PhotoPickerDialog class.
  */
 @RunWith(ChromeJUnit4ClassRunner.class)
+@MinAndroidSdkLevel(Build.VERSION_CODES.LOLLIPOP) // See crbug.com/888931 for details.
 @CommandLineFlags.Add({ChromeSwitches.DISABLE_FIRST_RUN_EXPERIENCE})
 public class PhotoPickerDialogTest implements PhotoPickerListener, SelectionObserver<PickerBitmap>,
                                               DecoderServiceHost.ServiceReadyCallback,
@@ -213,7 +214,6 @@ public class PhotoPickerDialogTest implements PhotoPickerListener, SelectionObse
     }
 
     @Test
-    @DisableIf.Build(sdk_is_less_than = Build.VERSION_CODES.LOLLIPOP, message = "crbug.com/888931")
     @LargeTest
     public void testNoSelection() throws Throwable {
         createDialog(false, Arrays.asList("image/*")); // Multi-select = false.
@@ -231,7 +231,6 @@ public class PhotoPickerDialogTest implements PhotoPickerListener, SelectionObse
     }
 
     @Test
-    @DisableIf.Build(sdk_is_less_than = Build.VERSION_CODES.LOLLIPOP, message = "crbug.com/888931")
     @LargeTest
     public void testSingleSelectionPhoto() throws Throwable {
         createDialog(false, Arrays.asList("image/*")); // Multi-select = false.
@@ -261,7 +260,6 @@ public class PhotoPickerDialogTest implements PhotoPickerListener, SelectionObse
     }
 
     @Test
-    @DisableIf.Build(sdk_is_less_than = Build.VERSION_CODES.LOLLIPOP, message = "crbug.com/888931")
     @LargeTest
     public void testMultiSelectionPhoto() throws Throwable {
         createDialog(true, Arrays.asList("image/*")); // Multi-select = true.

chrome/browser/android/chrome_feature_list.cc

@@ -158,6 +158,7 @@ const base::Feature* kFeaturesExposedToJava[] = {
     &kOverlayNewLayout,
     &kPayWithGoogleV1,
     &kPhotoPickerVideoSupport,
+    &kPhotoPickerZoom,
     &kReachedCodeProfiler,
     &kReaderModeInCCT,
     &kReorderBookmarks,
@@ -491,6 +492,9 @@ const base::Feature kPayWithGoogleV1{"PayWithGoogleV1",
 const base::Feature kPhotoPickerVideoSupport{"PhotoPickerVideoSupport",
                                              base::FEATURE_DISABLED_BY_DEFAULT};
 
+const base::Feature kPhotoPickerZoom{"PhotoPickerZoom",
+                                     base::FEATURE_DISABLED_BY_DEFAULT};
+
 const base::Feature kReachedCodeProfiler{"ReachedCodeProfiler",
                                          base::FEATURE_DISABLED_BY_DEFAULT};
 

chrome/browser/android/chrome_feature_list.h

@@ -91,6 +91,7 @@ extern const base::Feature kOmniboxSpareRenderer;
 extern const base::Feature kOverlayNewLayout;
 extern const base::Feature kPayWithGoogleV1;
 extern const base::Feature kPhotoPickerVideoSupport;
+extern const base::Feature kPhotoPickerZoom;
 extern const base::Feature kReachedCodeProfiler;
 extern const base::Feature kReorderBookmarks;
 extern const base::Feature kReaderModeInCCT;