[Download Notification] Show preview if downloaded file is image

chrome/browser/download/notification/download_notification_item_unittest.cc

Index: chrome/browser/download/notification/download_notification_item_unittest.cc
diff --git a/chrome/browser/download/notification/download_notification_item_unittest.cc b/chrome/browser/download/notification/download_notification_item_unittest.cc
index 9939f14acad69814f08c3ec6e2ae896f9ddbce3c..17da8c78e5f56bf32b322d59ccbd5bd310a4aa2c 100644
--- a/chrome/browser/download/notification/download_notification_item_unittest.cc
+++ b/chrome/browser/download/notification/download_notification_item_unittest.cc
@@ -22,6 +22,7 @@
 
 using testing::NiceMock;
 using testing::Return;
+using testing::ReturnRef;
 using testing::_;
 
 namespace {
@@ -67,6 +68,9 @@ class MockDownloadNotificationItemDelegate
   size_t on_download_stopped_call_count_;
 };
 
+const base::FilePath::CharType kDownloadItemTargetPathString[] =
+    FILE_PATH_LITERAL("/tmp/TITLE.bin");
+
 }  // anonymous namespace
 
 namespace test {
@@ -90,6 +94,7 @@ class DownloadNotificationItemTest : public testing::Test {
     DownloadNotificationItem::SetStubNotificationUIManagerForTesting(
         ui_manager_.get());
 
+    base::FilePath download_item_target_path(kDownloadItemTargetPathString);
     download_item_.reset(new NiceMock<content::MockDownloadItem>());
     ON_CALL(*download_item_, GetId()).WillByDefault(Return(12345));
     ON_CALL(*download_item_, GetState())
@@ -97,6 +102,8 @@ class DownloadNotificationItemTest : public testing::Test {
     ON_CALL(*download_item_, IsDangerous()).WillByDefault(Return(false));
     ON_CALL(*download_item_, GetFileNameToReportUser())
         .WillByDefault(Return(base::FilePath("TITLE.bin")));
+    ON_CALL(*download_item_, GetTargetFilePath())
+        .WillByDefault(ReturnRef(download_item_target_path));

[asanka, 2015/06/16 15:10:20]

You are returning a reference to a local variable. Use ReturnRefOfCopy()
instead.

     ON_CALL(*download_item_, GetDangerType())
         .WillByDefault(Return(content::DOWNLOAD_DANGER_TYPE_NOT_DANGEROUS));
     ON_CALL(*download_item_, IsDone()).WillByDefault(Return(false));