Add CF_HDROP path for dragging on Win Aura

content/browser/web_contents/web_contents_view_aura.cc

Index: content/browser/web_contents/web_contents_view_aura.cc
diff --git a/content/browser/web_contents/web_contents_view_aura.cc b/content/browser/web_contents/web_contents_view_aura.cc
index 6825fc677a477bd6ccf6747a37a4d362370b4035..6cacaacf75d8cfef930b368a12992da83afb1779 100644
--- a/content/browser/web_contents/web_contents_view_aura.cc
+++ b/content/browser/web_contents/web_contents_view_aura.cc
@@ -6,8 +6,10 @@
 
 #include "base/auto_reset.h"
 #include "base/command_line.h"
+#include "base/file_util.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/utf_string_conversions.h"
+#include "content/browser/download/drag_download_util.h"
 #include "content/browser/frame_host/interstitial_page_impl.h"
 #include "content/browser/frame_host/navigation_entry_impl.h"
 #include "content/browser/renderer_host/dip_util.h"
@@ -21,6 +23,7 @@
 #include "content/browser/web_contents/aura/window_slider.h"
 #include "content/browser/web_contents/touch_editable_impl_aura.h"
 #include "content/browser/web_contents/web_contents_impl.h"
+#include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/notification_source.h"
@@ -33,6 +36,7 @@
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_view_delegate.h"
 #include "content/public/browser/web_drag_dest_delegate.h"
+#include "content/public/common/content_client.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/drop_data.h"
 #include "net/base/net_util.h"
@@ -256,12 +260,75 @@ void PrepareDragForFileContents(const DropData& drop_data,
   }
   provider->SetFileContents(file_name, drop_data.file_contents);
 }
+
+void PrepareDragForDownload(
+    const DropData& drop_data,
+    ui::OSExchangeData::Provider* provider,
+    WebContentsImpl* web_contents) {
+  const GURL& page_url = web_contents->GetLastCommittedURL();
+  const std::string& page_encoding = web_contents->GetEncoding();
+
+  // Parse the download metadata.
+  base::string16 mime_type;
+  base::FilePath file_name;
+  GURL download_url;
+  if (!ParseDownloadMetadata(drop_data.download_metadata,
+                             &mime_type,
+                             &file_name,
+                             &download_url))
+    return;
+
+  // Generate the file name based on both mime type and proposed file name.
+  std::string default_name =
+      GetContentClient()->browser()->GetDefaultDownloadName();
+  base::FilePath generated_download_file_name =
+      net::GenerateFileName(download_url,
+                            std::string(),
+                            std::string(),
+                            base::UTF16ToUTF8(file_name.value()),
+                            base::UTF16ToUTF8(mime_type),
+                            default_name);
+
+  // http://crbug.com/332579
+  base::ThreadRestrictions::ScopedAllowIO allow_file_operations;
+
+  base::FilePath temp_dir_path;
+  if (!base::CreateNewTempDirectory(FILE_PATH_LITERAL("chrome_drag"),
+                                    &temp_dir_path))
+    return;
+  base::FilePath download_path =

[Ben Goodger (Google), 2014/01/11 05:01:47]

nit: nl above

[scottmg, 2014/01/11 05:02:46]

Done.

+      temp_dir_path.Append(generated_download_file_name);
+
+  // We cannot know when the target application will be done using the temporary
+  // file, so schedule it to be deleted after rebooting.
+  base::DeleteFileAfterReboot(download_path);
+  base::DeleteFileAfterReboot(temp_dir_path);
+
+  // Provide the data as file (CF_HDROP). A temporary download file with the
+  // Zone.Identifier ADS (Alternate Data Stream) attached will be created.
+  scoped_refptr<DragDownloadFile> download_file =
+      new DragDownloadFile(
+          download_path,
+          scoped_ptr<net::FileStream>(),
+          download_url,
+          Referrer(page_url, drop_data.referrer_policy),
+          page_encoding,
+          web_contents);
+  ui::OSExchangeData::DownloadFileInfo file_download(base::FilePath(),
+                                                     download_file.get());
+  provider->SetDownloadFileInfo(file_download);
+}
 #endif
 
 // Utility to fill a ui::OSExchangeDataProvider object from DropData.
 void PrepareDragData(const DropData& drop_data,
-                     ui::OSExchangeData::Provider* provider) {
+                     ui::OSExchangeData::Provider* provider,
+                     WebContentsImpl* web_contents) {
 #if defined(OS_WIN)
+  // Put download before file contents to prefer the download of a image over
+  // its thumbnail link.
+  if (!drop_data.download_metadata.empty())
+    PrepareDragForDownload(drop_data, provider, web_contents);
   // We set the file contents before the URL because the URL also sets file
   // contents (to a .URL shortcut).  We want to prefer file content data over
   // a shortcut so we add it first.
@@ -1368,7 +1435,7 @@ void WebContentsViewAura::StartDragging(
     touch_editable_->EndTouchEditing();
 
   ui::OSExchangeData::Provider* provider = ui::OSExchangeData::CreateProvider();
-  PrepareDragData(drop_data, provider);
+  PrepareDragData(drop_data, provider, web_contents_);
 
   ui::OSExchangeData data(provider);  // takes ownership of |provider|.