Revert of Refactor download image-MIME-type-detection code.

chrome/browser/download/download_item_model_unittest.cc

Index: chrome/browser/download/download_item_model_unittest.cc
diff --git a/chrome/browser/download/download_item_model_unittest.cc b/chrome/browser/download/download_item_model_unittest.cc
index 7325f00b07b25ae4eba581f975e7309a26d9b690..dfb07feff443ef48d4b1f11afa0a28ef4cd563c8 100644
--- a/chrome/browser/download/download_item_model_unittest.cc
+++ b/chrome/browser/download/download_item_model_unittest.cc
@@ -30,7 +30,6 @@
 using ::testing::Mock;
 using ::testing::NiceMock;
 using ::testing::Return;
-using ::testing::ReturnRef;
 using ::testing::ReturnRefOfCopy;
 using ::testing::SetArgPointee;
 using ::testing::_;
@@ -383,33 +382,6 @@
   EXPECT_EQ(DownloadFileType::ALLOW_ON_USER_GESTURE, model().GetDangerLevel());
 }
 
-TEST_F(DownloadItemModelTest, HasSupportedImageMimeType) {
-  SetupDownloadItemDefaults();
-
-  // When the item has a supported image MIME type, true should be returned.
-  ON_CALL(item(), GetMimeType()).WillByDefault(Return("image/png"));
-  EXPECT_TRUE(model().HasSupportedImageMimeType());
-
-  // An unsupported MIME type should result in false being returned...
-  ON_CALL(item(), GetMimeType()).WillByDefault(Return("image/unsupported"));
-  EXPECT_FALSE(model().HasSupportedImageMimeType());
-
-  // ... unless the target path has a well-known image extension.
-  const base::FilePath kImagePath(FILE_PATH_LITERAL("/foo/image.png"));
-  ON_CALL(item(), GetTargetFilePath()).WillByDefault(ReturnRef(kImagePath));
-  EXPECT_TRUE(model().HasSupportedImageMimeType());
-
-  // .txt and missing extensions should also result in false being returned.
-  const base::FilePath kTextPath(FILE_PATH_LITERAL("/foo/image.txt"));
-  ON_CALL(item(), GetTargetFilePath()).WillByDefault(ReturnRef(kTextPath));
-  EXPECT_FALSE(model().HasSupportedImageMimeType());
-
-  const base::FilePath kNoExtensionPath(FILE_PATH_LITERAL("/foo/image."));
-  ON_CALL(item(), GetTargetFilePath())
-      .WillByDefault(ReturnRef(kNoExtensionPath));
-  EXPECT_FALSE(model().HasSupportedImageMimeType());
-}
-
 TEST_F(DownloadItemModelTest, ShouldRemoveFromShelfWhenComplete) {
   const struct TestCase {
     DownloadItem::DownloadState state;