Ask download manager to remove a download if it is overwritten by another

chrome/browser/android/download/download_manager_service.cc

Index: chrome/browser/android/download/download_manager_service.cc
diff --git a/chrome/browser/android/download/download_manager_service.cc b/chrome/browser/android/download/download_manager_service.cc
index f00173594033be98ce8d3a58358bbd1f0e705993..08dd6e3e45f56a32933fd10f2fd3f18458172753 100644
--- a/chrome/browser/android/download/download_manager_service.cc
+++ b/chrome/browser/android/download/download_manager_service.cc
@@ -44,6 +44,23 @@ void updateNotifier(DownloadManagerService* service,
   }
 }
 
+void RemoveDownloadsFromDownloadManager(
+    content::DownloadManager* manager,
+    const base::FilePath& path) {
+  if (!manager)
+    return;
+  content::DownloadManager::DownloadVector all_items;
+  manager->GetAllDownloads(&all_items);
+
+  for (size_t i = 0; i < all_items.size(); i++) {
+    content::DownloadItem* item = all_items[i];
+    if (item->GetState() == content::DownloadItem::COMPLETE &&

[Theresa, 2016/09/21 17:40:43]

Is it possible to interleave downloading items with the same path e.g. download
really_big_video.mp4 3x in a row, overwriting each time. I'm wondering if it's
possible that checking DownloadItem::COMPLETE will leave pending downloads that
all reference the same path?

[qinmin, 2016/09/21 21:20:29]

If a download starts (or resumes) with the same target path as another ongoing
download, the new comer will fail.
So multiple ongoing downloads cannot have the same target path.

+        item->GetTargetFilePath() == path) {
+      item->Remove();
+    }
+  }
+}
+
 }  // namespace
 
 // static
@@ -65,11 +82,15 @@ void DownloadManagerService::OnDownloadCanceled(
   DownloadController::RecordDownloadCancelReason(reason);
 }
 
+// static
+DownloadManagerService* DownloadManagerService::GetInstance() {
+  return base::Singleton<DownloadManagerService>::get();
+}
 
 static jlong Init(JNIEnv* env, const JavaParamRef<jobject>& jobj) {
   Profile* profile = ProfileManager::GetActiveUserProfile();
-  DownloadManagerService* service =
-      new DownloadManagerService(env, jobj);
+  DownloadManagerService* service = DownloadManagerService::GetInstance();
+  service->Init(env, jobj);
   DownloadService* download_service =
       DownloadServiceFactory::GetForBrowserContext(profile);
   DownloadHistory* history = download_service->GetDownloadHistory();
@@ -78,17 +99,20 @@ static jlong Init(JNIEnv* env, const JavaParamRef<jobject>& jobj) {
   return reinterpret_cast<intptr_t>(service);
 }
 
-DownloadManagerService::DownloadManagerService(
+DownloadManagerService::DownloadManagerService()
+    : is_history_query_complete_(false) {
+}
+
+DownloadManagerService::~DownloadManagerService() {}
+
+void DownloadManagerService::Init(
     JNIEnv* env,
-    jobject obj)
-    : java_ref_(env, obj),
-      is_history_query_complete_(false) {
+    jobject obj) {
+  java_ref_.Reset(env, obj);
   DownloadControllerBase::Get()->SetDefaultDownloadFileName(
       l10n_util::GetStringUTF8(IDS_DEFAULT_DOWNLOAD_FILENAME));
 }
 
-DownloadManagerService::~DownloadManagerService() {}
-
 void DownloadManagerService::ResumeDownload(
     JNIEnv* env,
     jobject obj,
@@ -185,6 +209,14 @@ void DownloadManagerService::CheckForExternallyRemovedDownloads(
   manager->CheckForHistoryFilesRemoval();
 }
 
+void DownloadManagerService::RemoveExternallyRemovedDownloads(
+    const base::FilePath& path) {
+  content::DownloadManager* manager = GetDownloadManager(false);
+  RemoveDownloadsFromDownloadManager(manager, path);
+  manager = GetDownloadManager(true);
+  RemoveDownloadsFromDownloadManager(manager, path);
+}
+
 void DownloadManagerService::CancelDownload(
     JNIEnv* env,
     jobject obj,