reintroduce InterceptDownloadResourceThrottle for some OMA DRM downloads

chrome/browser/android/download/download_controller.cc

Index: chrome/browser/android/download/download_controller.cc
diff --git a/chrome/browser/android/download/download_controller.cc b/chrome/browser/android/download/download_controller.cc
index c77b0f282df2296204a05c8ee2f9d44748d1b436..f66003049499ef2a4fb85de63f1d170b4529042f 100644
--- a/chrome/browser/android/download/download_controller.cc
+++ b/chrome/browser/android/download/download_controller.cc
@@ -219,6 +219,54 @@ void DownloadController::AcquireFileAccessPermission(
       RequestFileAccess(callback_id);
 }
 
+void DownloadController::CreateGETDownload(
+    const content::ResourceRequestInfo::WebContentsGetter& wc_getter,
+    const DownloadInfo& info) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      base::Bind(&DownloadController::StartAndroidDownload,
+                 base::Unretained(this),
+                 wc_getter, info));
+}
+
+void DownloadController::StartAndroidDownload(
+    const content::ResourceRequestInfo::WebContentsGetter& wc_getter,
+    const DownloadInfo& info) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  WebContents* web_contents = wc_getter.Run();
+  if (!web_contents) {
+    // The view went away. Can't proceed.
+    LOG(ERROR) << "Download failed on URL:" << info.url.spec();
+    return;
+  }
+
+  AcquireFileAccessPermission(
+      web_contents,
+      base::Bind(&DownloadController::StartAndroidDownloadInternal,
+                 base::Unretained(this), wc_getter, info));
+}
+
+void DownloadController::StartAndroidDownloadInternal(
+    const content::ResourceRequestInfo::WebContentsGetter& wc_getter,
+    const DownloadInfo& info, bool allowed) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  if (!allowed)
+    return;
+
+  WebContents* web_contents = wc_getter.Run();
+  if (!web_contents)
+    return;

[David Trainor- moved to gerrit, 2017/01/24 17:13:35]

Should this case log a similar error to StartAndroidDownload()?

[qinmin, 2017/01/24 17:32:23]

Done.

+
+  ChromeDownloadDelegate::FromWebContents(web_contents)->
+      EnqueueDownloadManagerRequest(
+          info.url.spec(), info.user_agent,
+          info.content_disposition, info.original_mime_type,
+          info.cookie, info.referer);
+}
+
 bool DownloadController::HasFileAccessPermission(
     ui::WindowAndroid* window_android) {
   ScopedJavaLocalRef<jobject> jwindow_android = window_android->GetJavaObject();