Download location: Don't delete DB record for missing files on SD card.

If the user pulls out the SD card, currently the download database
record will be removed and user can no longer see the download.

Instead, we shouldn't erase the database records for files on SD card
when checking if they are externally removed. Later we can add a timestamp
to persist the time when the file is found missing for the first time, and
erase the db record 30 days after this timestamp.

TBR=mpearson@chromium.org

Bug: 845369
Change-Id: I5b129df435119d501867cedde85ef49ec844aa38
Reviewed-on: https://chromium-review.googlesource.com/1068273
Commit-Queue: Xing Liu <xingliu@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Cr-Commit-Position: refs/heads/master@{#561369}

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

@@ -10,6 +10,7 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.res.ColorStateList;
 import android.net.Uri;
+import android.os.Environment;
 import android.os.StrictMode;
 import android.support.annotation.IntDef;
 import android.support.annotation.Nullable;
@@ -22,6 +23,7 @@ import org.chromium.base.ContextUtils;
 import org.chromium.base.FileUtils;
 import org.chromium.base.Log;
 import org.chromium.base.PathUtils;
+import org.chromium.base.StrictModeContext;
 import org.chromium.base.VisibleForTesting;
 import org.chromium.base.library_loader.LibraryProcessType;
 import org.chromium.base.metrics.RecordHistogram;
@@ -1066,4 +1068,18 @@ public class DownloadUtils {
     public static String[] getAllDownloadDirectories() {
         return PathUtils.getAllPrivateDownloadsDirectories();
     }
+
+    /**
+     * Returns if the path is in the download directory on primary storage.
+     * @param path The directory to check.
+     * @return If the path is in the download directory on primary storage.
+     */
+    public static boolean isInPrimaryStorageDownloadDirectory(String path) {
+        StrictModeContext c = StrictModeContext.allowDiskReads();
+        File primaryDir = Environment.getExternalStorageDirectory();
+        if (primaryDir == null || path == null) return false;
+        String primaryPath = primaryDir.getAbsolutePath();
+        if (primaryPath == null) return false;
+        return path.contains(primaryPath);
+    }
 }

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

@@ -309,15 +309,19 @@ public class DownloadHistoryAdapter extends DateDividedAdapter
         //                    downloads rather than passing them to Java.
         if (sDeletedFileTracker.contains(wrapper)) return true;
 
-        if (wrapper.hasBeenExternallyRemoved()) {
+        if (!wrapper.hasBeenExternallyRemoved()) return false;
+
+        if (DownloadUtils.isInPrimaryStorageDownloadDirectory(wrapper.getFilePath())) {
             sDeletedFileTracker.add(wrapper);
             wrapper.removePermanently();
             mFilePathsToItemsMap.removeItem(wrapper);
             RecordUserAction.record("Android.DownloadManager.Item.ExternallyDeleted");
             return true;
+        } else {
+            // Keeps the download record when the file is on external SD card.
+            RecordUserAction.record("Android.DownloadManager.Item.ExternallyDeletedKeepRecord");
+            return false;
         }
-
-        return false;
     }
 
     private boolean addDownloadHistoryItemWrapper(DownloadHistoryItemWrapper wrapper) {

chrome/android/javatests/src/org/chromium/chrome/browser/download/ui/StubbedProvider.java

@@ -7,6 +7,7 @@ package org.chromium.chrome.browser.download.ui;
 import static junit.framework.Assert.assertEquals;
 import static junit.framework.Assert.assertNull;
 
+import android.os.Environment;
 import android.os.Handler;
 import android.os.Looper;
 
@@ -296,13 +297,15 @@ public class StubbedProvider implements BackendProvider {
                     .setDownloadGuid("sixth_guid")
                     .setMimeType("audio/mp3");
         } else if (which == 6) {
-            builder = new DownloadInfo.Builder()
-                    .setUrl("https://sigh.com")
-                    .setBytesReceived(ONE_GIGABYTE)
-                    .setFileName("huge_image.png")
-                    .setFilePath("/storage/fake_path/Downloads/huge_image.png")
-                    .setDownloadGuid("seventh_guid")
-                    .setMimeType("image/png");
+            builder =
+                    new DownloadInfo.Builder()
+                            .setUrl("https://sigh.com")
+                            .setBytesReceived(ONE_GIGABYTE)
+                            .setFileName("huge_image.png")
+                            .setFilePath(Environment.getExternalStorageDirectory().getAbsolutePath()
+                                    + "/fake_path/Downloads/huge_image.png")
+                            .setDownloadGuid("seventh_guid")
+                            .setMimeType("image/png");
         } else if (which == 7) {
             builder = new DownloadInfo.Builder()
                     .setUrl("https://sleepy.com")

tools/metrics/actions/actions.xml

@@ -1568,8 +1568,18 @@ should be able to be added at any place in this file.
   <owner>dtrainor@chromium.org</owner>
   <owner>twellington@chromium.org</owner>
   <description>
-    A download tracked by the Chrome download service was externally deleted
-    e.g. through a third-party download manager.
+    A download file on primary storage was externally deleted by other
+    application. e.g. through a third-party download manager. The associated
+    database record will be also deleted.
+  </description>
+</action>
+
+<action name="Android.DownloadManager.Item.ExternallyDeletedKeepRecord">
+  <owner>xingliu@chromium.org</owner>
+  <description>
+    A download file was externally deleted by other application, e.g. through a
+    third-party download manager. However the associated database record will
+    not be immediately deleted.
   </description>
 </action>