reintroduce InterceptDownloadResourceThrottle for some OMA DRM downloads

chrome/browser/android/download/mock_download_controller.h

Index: chrome/browser/android/download/mock_download_controller.h
diff --git a/chrome/browser/android/download/mock_download_controller.h b/chrome/browser/android/download/mock_download_controller.h
index 291329462453f4d1d3d66723b5e8d4e05baad1a2..5f5d32e814c4014eb3d9558c8f311787d953fb2c 100644
--- a/chrome/browser/android/download/mock_download_controller.h
+++ b/chrome/browser/android/download/mock_download_controller.h
@@ -34,7 +34,9 @@ class MockDownloadController : public DownloadControllerBase {
       content::WebContents* web_contents,
       const AcquireFileAccessPermissionCallback& callback) override;
   void SetApproveFileAccessRequestForTesting(bool approve) override;
-
+  void CreateGETDownload(
+      const content::ResourceRequestInfo::WebContentsGetter& wc_getter,
+      const DownloadInfo& info) override;
  private:
   bool approve_file_access_request_;
   DISALLOW_COPY_AND_ASSIGN(MockDownloadController);