Simplify AwDownloadManagerDelegate

With the NetworkService, InterceptDownloadIfApplicable is always called
on the UI thread.

Remove some overrides that are unnecessary, and unconditionally intercept
downloads --- rather than missing some, and cancelling them in
DetermineDownloadTarget.

Bug: none
Change-Id: Ia85f420d7d7aca3d14823e1d38d597e07bbf3f51
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1866551Reviewed-by: Richard Coles <torne@chromium.org>
Reviewed-by: Tim Volodine <timvolodine@chromium.org>
Commit-Queue: Evan Stade <estade@chromium.org>
Cr-Commit-Position: refs/heads/master@{#707519}

android_webview/browser/aw_download_manager_delegate.cc

@@ -6,62 +6,14 @@
 
 #include "android_webview/browser/aw_content_browser_client.h"
 #include "android_webview/browser/aw_contents_client_bridge.h"
-#include "base/files/file_path.h"
-#include "base/task/post_task.h"
-#include "components/download/public/common/download_danger_type.h"
-#include "components/download/public/common/download_item.h"
 #include "content/public/browser/browser_task_traits.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/web_contents.h"
 
 namespace android_webview {
 
-namespace {
-
-void DownloadStartingOnUIThread(content::WebContents* web_contents,
-                                const GURL& url,
-                                const std::string& user_agent,
-                                const std::string& content_disposition,
-                                const std::string& mime_type,
-                                int64_t content_length) {
-  AwContentsClientBridge* client =
-      AwContentsClientBridge::FromWebContents(web_contents);
-  if (!client)
-    return;
-  client->NewDownload(url, user_agent, content_disposition, mime_type,
-                      content_length);
-}
-
-}  // namespace
-
-AwDownloadManagerDelegate::~AwDownloadManagerDelegate() {}
-
-bool AwDownloadManagerDelegate::DetermineDownloadTarget(
-    download::DownloadItem* item,
-    const content::DownloadTargetCallback& callback) {
-  // Note this cancel is independent of the URLRequest cancel in
-  // AwResourceDispatcherHostDelegate::DownloadStarting. The request
-  // could have already finished by the time DownloadStarting is called.
-  callback.Run(base::FilePath() /* Empty file path for cancel */,
-               download::DownloadItem::TARGET_DISPOSITION_OVERWRITE,
-               download::DOWNLOAD_DANGER_TYPE_NOT_DANGEROUS, base::FilePath(),
-               download::DOWNLOAD_INTERRUPT_REASON_USER_CANCELED);
-  return true;
-}
-
-bool AwDownloadManagerDelegate::ShouldCompleteDownload(
-    download::DownloadItem* item,
-    base::OnceClosure complete_callback) {
-  NOTREACHED();
-  return true;
-}
-
-bool AwDownloadManagerDelegate::ShouldOpenDownload(
-    download::DownloadItem* item,
-    const content::DownloadOpenDelayedCallback& callback) {
-  NOTREACHED();
-  return true;
-}
+AwDownloadManagerDelegate::AwDownloadManagerDelegate() = default;
+AwDownloadManagerDelegate::~AwDownloadManagerDelegate() = default;
 
 bool AwDownloadManagerDelegate::InterceptDownloadIfApplicable(
     const GURL& url,
@@ -72,25 +24,24 @@ bool AwDownloadManagerDelegate::InterceptDownloadIfApplicable(
     int64_t content_length,
     bool is_transient,
     content::WebContents* web_contents) {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (!web_contents)
-    return false;
+    return true;
+
+  AwContentsClientBridge* client =
+      AwContentsClientBridge::FromWebContents(web_contents);
+  if (!client)
+    return true;
 
   std::string aw_user_agent = web_contents->GetUserAgentOverride();
   if (aw_user_agent.empty()) {
     // use default user agent if nothing is provided
     aw_user_agent = user_agent.empty() ? GetUserAgent() : user_agent;
   }
-  base::PostTask(FROM_HERE, {content::BrowserThread::UI},
-                 base::BindOnce(&DownloadStartingOnUIThread, web_contents, url,
-                                aw_user_agent, content_disposition, mime_type,
-                                content_length));
-  return true;
-}
 
-void AwDownloadManagerDelegate::GetNextId(
-    const content::DownloadIdCallback& callback) {
-  static uint32_t next_id = download::DownloadItem::kInvalidId + 1;
-  callback.Run(next_id++);
+  client->NewDownload(url, aw_user_agent, content_disposition, mime_type,
+                      content_length);
+  return true;
 }
 
 }  // namespace android_webview

android_webview/browser/aw_download_manager_delegate.h

@@ -7,6 +7,7 @@
 
 #include <string>
 
+#include "base/macros.h"
 #include "base/supports_user_data.h"
 #include "content/public/browser/download_manager_delegate.h"
 
@@ -23,17 +24,10 @@ namespace android_webview {
 class AwDownloadManagerDelegate : public content::DownloadManagerDelegate,
                                   public base::SupportsUserData::Data {
  public:
+  AwDownloadManagerDelegate();
   ~AwDownloadManagerDelegate() override;
 
   // content::DownloadManagerDelegate implementation.
-  bool DetermineDownloadTarget(
-      download::DownloadItem* item,
-      const content::DownloadTargetCallback& callback) override;
-  bool ShouldCompleteDownload(download::DownloadItem* item,
-                              base::OnceClosure complete_callback) override;
-  bool ShouldOpenDownload(
-      download::DownloadItem* item,
-      const content::DownloadOpenDelayedCallback& callback) override;
   bool InterceptDownloadIfApplicable(
       const GURL& url,
       const std::string& user_agent,
@@ -43,7 +37,9 @@ class AwDownloadManagerDelegate : public content::DownloadManagerDelegate,
       int64_t content_length,
       bool is_transient,
       content::WebContents* web_contents) override;
-  void GetNextId(const content::DownloadIdCallback& callback) override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(AwDownloadManagerDelegate);
 };
 
 }  // namespace android_webview