chrome: Add CefDownloadHandler support (see #3681)

Behaves the same as Alloy runtime except that CanDownload is not
called for invalid protocol schemes.

BUILD.gn

@@ -465,6 +465,8 @@ source_set("libcef_static") {
     "libcef/browser/alloy/alloy_browser_main.h",
     "libcef/browser/alloy/alloy_content_browser_client.cc",
     "libcef/browser/alloy/alloy_content_browser_client.h",
+    "libcef/browser/alloy/alloy_download_manager_delegate.cc",
+    "libcef/browser/alloy/alloy_download_manager_delegate.h",
     "libcef/browser/alloy/alloy_download_util.cc",
     "libcef/browser/alloy/alloy_download_util.h",
     "libcef/browser/alloy/alloy_web_contents_view_delegate.cc",
@@ -576,6 +578,8 @@ source_set("libcef_static") {
     "libcef/browser/download_item_impl.h",
     "libcef/browser/download_manager_delegate.cc",
     "libcef/browser/download_manager_delegate.h",
+    "libcef/browser/download_manager_delegate_impl.cc",
+    "libcef/browser/download_manager_delegate_impl.h",
     "libcef/browser/extension_impl.cc",
     "libcef/browser/extension_impl.h",
     "libcef/browser/extensions/api/file_system/cef_file_system_delegate.cc",

include/capi/cef_download_handler_capi.h

@@ -33,7 +33,7 @@
 // by hand. See the translator.README.txt file in the tools directory for
 // more information.
 //
-// $hash=60a08a60be70e8fe5df17f18f8e5758e1830d5e1$
+// $hash=7ecfb07a95315ff81937e9f68d419122fc88f1b7$
 //
 
 #ifndef CEF_INCLUDE_CAPI_CEF_DOWNLOAD_HANDLER_CAPI_H_
@@ -117,12 +117,13 @@ typedef struct _cef_download_handler_t {
 
   ///
   /// Called before a download begins. |suggested_name| is the suggested name
-  /// for the download file. By default the download will be canceled. Execute
-  /// |callback| either asynchronously or in this function to continue the
-  /// download if desired. Do not keep a reference to |download_item| outside of
-  /// this function.
+  /// for the download file. Return true (1) and execute |callback| either
+  /// asynchronously or in this function to continue or cancel the download.
+  /// Return false (0) to proceed with default handling (cancel with Alloy
+  /// style, download shelf with Chrome style). Do not keep a reference to
+  /// |download_item| outside of this function.
   ///
-  void(CEF_CALLBACK* on_before_download)(
+  int(CEF_CALLBACK* on_before_download)(
       struct _cef_download_handler_t* self,
       struct _cef_browser_t* browser,
       struct _cef_download_item_t* download_item,

include/cef_api_hash.h

@@ -42,13 +42,13 @@
 // way that may cause binary incompatibility with other builds. The universal
 // hash value will change if any platform is affected whereas the platform hash
 // values will change only if that particular platform is affected.
-#define CEF_API_HASH_UNIVERSAL "faa8a52df058a26e1228da66052a9900a7120de4"
+#define CEF_API_HASH_UNIVERSAL "73e8743408bfeba0df3b567bfd04b2eb642df11d"
 #if defined(OS_WIN)
-#define CEF_API_HASH_PLATFORM "41a15a683e4a2b927f043c22d8a9f07671168170"
+#define CEF_API_HASH_PLATFORM "3a73f4c69062c6f413e00c1821f6e6df91a2a787"
 #elif defined(OS_MAC)
-#define CEF_API_HASH_PLATFORM "6933ff4566b919c045ff0743682889d45ffcba28"
+#define CEF_API_HASH_PLATFORM "f5fb92747082f06a9c42724b0b717accc29e3879"
 #elif defined(OS_LINUX)
-#define CEF_API_HASH_PLATFORM "b12778ab8fd0974e45a246484a31d12f097c7936"
+#define CEF_API_HASH_PLATFORM "8775d620c6b17725bddba2c1c3a21353b4d8acb1"
 #endif
 
 #ifdef __cplusplus

include/cef_download_handler.h

@@ -106,17 +106,19 @@ class CefDownloadHandler : public virtual CefBaseRefCounted {
 
   ///
   /// Called before a download begins. |suggested_name| is the suggested name
-  /// for the download file. By default the download will be canceled. Execute
-  /// |callback| either asynchronously or in this method to continue the
-  /// download if desired. Do not keep a reference to |download_item| outside of
-  /// this method.
+  /// for the download file. Return true and execute |callback| either
+  /// asynchronously or in this method to continue or cancel the download.
+  /// Return false to proceed with default handling (cancel with Alloy style,
+  /// download shelf with Chrome style). Do not keep a reference to
+  /// |download_item| outside of this method.
   ///
   /*--cef()--*/
-  virtual void OnBeforeDownload(
-      CefRefPtr<CefBrowser> browser,
-      CefRefPtr<CefDownloadItem> download_item,
-      const CefString& suggested_name,
-      CefRefPtr<CefBeforeDownloadCallback> callback) = 0;
+  virtual bool OnBeforeDownload(CefRefPtr<CefBrowser> browser,
+                                CefRefPtr<CefDownloadItem> download_item,
+                                const CefString& suggested_name,
+                                CefRefPtr<CefBeforeDownloadCallback> callback) {
+    return false;
+  }
 
   ///
   /// Called when a download's status or progress information has been updated.

libcef/browser/alloy/alloy_browser_context.cc

@@ -8,7 +8,7 @@
 #include <memory>
 #include <utility>
 
-#include "libcef/browser/download_manager_delegate.h"
+#include "libcef/browser/alloy/alloy_download_manager_delegate.h"
 #include "libcef/browser/extensions/extension_system.h"
 #include "libcef/browser/prefs/browser_prefs.h"
 #include "libcef/browser/ssl_host_state_delegate.h"
@@ -336,7 +336,7 @@ content::DownloadManagerDelegate*
 AlloyBrowserContext::GetDownloadManagerDelegate() {
   if (!download_manager_delegate_) {
     download_manager_delegate_ =
-        std::make_unique<CefDownloadManagerDelegate>(GetDownloadManager());
+        std::make_unique<AlloyDownloadManagerDelegate>(GetDownloadManager());
   }
   return download_manager_delegate_.get();
 }

libcef/browser/alloy/alloy_browser_context.h

@@ -15,7 +15,7 @@
 #include "components/proxy_config/pref_proxy_config_tracker.h"
 #include "components/visitedlink/browser/visitedlink_delegate.h"
 
-class CefDownloadManagerDelegate;
+class AlloyDownloadManagerDelegate;
 class CefSSLHostStateDelegate;
 class CefVisitedLinkListener;
 class PrefService;
@@ -128,7 +128,7 @@ class AlloyBrowserContext : public ChromeProfileAlloy,
   std::unique_ptr<PrefService> pref_service_;
   std::unique_ptr<PrefProxyConfigTracker> pref_proxy_config_tracker_;
 
-  std::unique_ptr<CefDownloadManagerDelegate> download_manager_delegate_;
+  std::unique_ptr<AlloyDownloadManagerDelegate> download_manager_delegate_;
   std::unique_ptr<CefSSLHostStateDelegate> ssl_host_state_delegate_;
   std::unique_ptr<visitedlink::VisitedLinkWriter> visitedlink_master_;
   // |visitedlink_listener_| is owned by visitedlink_master_.

libcef/browser/alloy/alloy_download_manager_delegate.cc

@@ -0,0 +1,22 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "libcef/browser/alloy/alloy_download_manager_delegate.h"
+
+#include "chrome/common/chrome_constants.h"
+#include "components/download/public/common/download_item.h"
+
+AlloyDownloadManagerDelegate::AlloyDownloadManagerDelegate(
+    content::DownloadManager* manager)
+    : CefDownloadManagerDelegateImpl(manager, /*alloy_bootstrap=*/true) {}
+
+void AlloyDownloadManagerDelegate::GetNextId(
+    content::DownloadIdCallback callback) {
+  static uint32_t next_id = download::DownloadItem::kInvalidId + 1;
+  std::move(callback).Run(next_id++);
+}
+
+std::string AlloyDownloadManagerDelegate::ApplicationClientIdForFileScanning() {
+  return std::string(chrome::kApplicationClientIDStringForAVScanning);
+}

libcef/browser/alloy/alloy_download_manager_delegate.h

@@ -0,0 +1,26 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CEF_LIBCEF_BROWSER_ALLOY_ALLOY_DOWNLOAD_MANAGER_DELEGATE_H_
+#define CEF_LIBCEF_BROWSER_ALLOY_ALLOY_DOWNLOAD_MANAGER_DELEGATE_H_
+#pragma once
+
+#include "libcef/browser/download_manager_delegate_impl.h"
+
+// Specialization for the Alloy bootstrap.
+class AlloyDownloadManagerDelegate : public CefDownloadManagerDelegateImpl {
+ public:
+  explicit AlloyDownloadManagerDelegate(content::DownloadManager* manager);
+
+  AlloyDownloadManagerDelegate(const AlloyDownloadManagerDelegate&) = delete;
+  AlloyDownloadManagerDelegate& operator=(const AlloyDownloadManagerDelegate&) =
+      delete;
+
+ private:
+  // DownloadManagerDelegate methods.
+  void GetNextId(content::DownloadIdCallback callback) override;
+  std::string ApplicationClientIdForFileScanning() override;
+};
+
+#endif  // CEF_LIBCEF_BROWSER_ALLOY_ALLOY_DOWNLOAD_MANAGER_DELEGATE_H_