Download: Create a delegate class to query directory from Android.

This CL adds a delegate class in DownloadDirectoryProvider, so we can
mock this behavior in test.

This is needed for the DownloadContentProvider effort for testing
purposes.

Bug: 970072
Change-Id: I585e51f60d5a356ffe1b5cb0116e615ceababad0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1663249Reviewed-by: Min Qin <qinmin@chromium.org>
Commit-Queue: Xing Liu <xingliu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#670243}

chrome/android/java/src/org/chromium/chrome/browser/download/DownloadDirectoryProvider.java

@@ -13,6 +13,7 @@ import android.os.Environment;
 
 import org.chromium.base.Callback;
 import org.chromium.base.ContextUtils;
+import org.chromium.base.Log;
 import org.chromium.base.PathUtils;
 import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.base.task.AsyncTask;
@@ -35,6 +36,41 @@ import java.util.ArrayList;
  * options accordingly.
  */
 public class DownloadDirectoryProvider {
+    private static final String TAG = "DownloadDirectory";
+
+    /**
+     * Delegate class to query directories from Android API. Should be created on main thread
+     * and used on background thread in {@link AsyncTask}.
+     */
+    public interface Delegate {
+        /**
+         * Get the primary download directory in public external storage. The directory will be
+         * created if it doesn't exist. Should be called on background thread.
+         * @return The download directory. Can be an invalid directory if failed to create the
+         *         directory.
+         */
+        File getPrimaryDownloadDirectory();
+
+        /**
+         * Get external files directories for {@link Environment#DIRECTORY_DOWNLOADS}.
+         * @return A list of directories.
+         */
+        File[] getExternalFilesDirs();
+    }
+
+    private static class DownloadDirectoryProviderDelegate implements Delegate {
+        @Override
+        public File getPrimaryDownloadDirectory() {
+            return DownloadDirectoryProvider.getPrimaryDownloadDirectory();
+        }
+
+        @Override
+        public File[] getExternalFilesDirs() {
+            return ContextUtils.getApplicationContext().getExternalFilesDirs(
+                    Environment.DIRECTORY_DOWNLOADS);
+        }
+    }
+
     /**
      * Asynchronous task to retrieve all download directories on a background thread. Only one task
      * can exist at the same time.
@@ -43,12 +79,18 @@ public class DownloadDirectoryProvider {
      * {@link PathUtils#getAllPrivateDownloadsDirectories}.
      */
     private class AllDirectoriesTask extends AsyncTask<ArrayList<DirectoryOption>> {
+        private DownloadDirectoryProvider.Delegate mDelegate;
+
+        AllDirectoriesTask(DownloadDirectoryProvider.Delegate delegate) {
+            mDelegate = delegate;
+        }
+
         @Override
         protected ArrayList<DirectoryOption> doInBackground() {
             ArrayList<DirectoryOption> dirs = new ArrayList<>();
 
             // Retrieve default directory.
-            File defaultDirectory = DownloadUtils.getPrimaryDownloadDirectory();
+            File defaultDirectory = mDelegate.getPrimaryDownloadDirectory();
 
             // If no default directory, return an error option.
             if (defaultDirectory == null) {
@@ -67,8 +109,7 @@ public class DownloadDirectoryProvider {
             File[] files;
 
             if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
-                files = ContextUtils.getApplicationContext().getExternalFilesDirs(
-                        Environment.DIRECTORY_DOWNLOADS);
+                files = mDelegate.getExternalFilesDirs();
             } else {
                 files = new File[] {Environment.getExternalStorageDirectory()};
             }
@@ -192,11 +233,32 @@ public class DownloadDirectoryProvider {
         return null;
     }
 
+    /**
+     * Get the primary download directory in public external storage. The directory will be created
+     * if it doesn't exist. Should be called on background thread.
+     * @return The download directory. Can be an invalid directory if failed to create the
+     *         directory.
+     */
+    public static File getPrimaryDownloadDirectory() {
+        File downloadDir =
+                Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
+
+        // Create the directory if needed.
+        if (!downloadDir.exists()) {
+            try {
+                downloadDir.mkdirs();
+            } catch (SecurityException e) {
+                Log.e(TAG, "Exception when creating download directory.", e);
+            }
+        }
+        return downloadDir;
+    }
+
     private void updateDirectories() {
         // If asynchronous task is pending, wait for its result.
         if (mAllDirectoriesTask != null) return;
 
-        mAllDirectoriesTask = new AllDirectoriesTask();
+        mAllDirectoriesTask = new AllDirectoriesTask(new DownloadDirectoryProviderDelegate());
         mAllDirectoriesTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
     }
 

chrome/android/java/src/org/chromium/chrome/browser/download/DownloadUtils.java

@@ -1216,27 +1216,6 @@ public class DownloadUtils {
         return primaryPath == null ? false : path.contains(primaryPath);
     }
 
-    /**
-     * Get the primary download directory in public external storage. The directory will be created
-     * if it doesn't exist.
-     * @return The download directory. Can be an invalid directory if failed to create the
-     *         directory.
-     */
-    public static File getPrimaryDownloadDirectory() {
-        File downloadDir =
-                Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
-
-        // Create the directory if needed.
-        if (!downloadDir.exists()) {
-            try {
-                downloadDir.mkdirs();
-            } catch (SecurityException e) {
-                Log.e(TAG, "Exception when creating download directory.", e);
-            }
-        }
-        return downloadDir;
-    }
-
     /**
      * Parses an originating URL string and returns a valid Uri that can be inserted into
      * DownloadProvider. The returned Uri has to be null or non-empty http(s) scheme.

chrome/android/java/src/org/chromium/chrome/browser/download/home/storage/StorageSummaryProvider.java

@@ -10,6 +10,7 @@ import android.support.annotation.Nullable;
 import org.chromium.base.task.AsyncTask;
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.download.DirectoryOption;
+import org.chromium.chrome.browser.download.DownloadDirectoryProvider;
 import org.chromium.chrome.browser.download.DownloadUtils;
 import org.chromium.chrome.browser.download.home.filter.OfflineItemFilterObserver;
 import org.chromium.chrome.browser.download.home.filter.OfflineItemFilterSource;
@@ -88,7 +89,7 @@ public class StorageSummaryProvider implements OfflineItemFilterObserver {
         new AsyncTask<DirectoryOption>() {
             @Override
             protected DirectoryOption doInBackground() {
-                File defaultDownloadDir = DownloadUtils.getPrimaryDownloadDirectory();
+                File defaultDownloadDir = DownloadDirectoryProvider.getPrimaryDownloadDirectory();
                 DirectoryOption directoryOption = new DirectoryOption("",
                         defaultDownloadDir.getAbsolutePath(), defaultDownloadDir.getUsableSpace(),
                         defaultDownloadDir.getTotalSpace(),

chrome/android/java/src/org/chromium/chrome/browser/download/ui/SpaceDisplay.java

@@ -19,6 +19,7 @@ import org.chromium.base.ObserverList;
 import org.chromium.base.VisibleForTesting;
 import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.base.task.AsyncTask;
+import org.chromium.chrome.browser.download.DownloadDirectoryProvider;
 import org.chromium.chrome.browser.download.DownloadUtils;
 import org.chromium.chrome.browser.widget.MaterialProgressBar;
 import org.chromium.chrome.download.R;
@@ -62,7 +63,7 @@ public class SpaceDisplay extends RecyclerView.AdapterDataObserver {
 
         @Override
         protected Long doInBackground() {
-            File downloadDirectory = DownloadUtils.getPrimaryDownloadDirectory();
+            File downloadDirectory = DownloadDirectoryProvider.getPrimaryDownloadDirectory();
 
             // Determine how much space is available on the storage device where downloads
             // reside.  If the downloads directory doesn't exist, it is likely that the user