Mark drags starting in web content as tainted to avoid file path forgery

ui/base/dragdrop/gtk_dnd_util.cc

Index: ui/base/dragdrop/gtk_dnd_util.cc
diff --git a/ui/base/dragdrop/gtk_dnd_util.cc b/ui/base/dragdrop/gtk_dnd_util.cc
index 163dce43c64682c8547c00ba5f6202df3caf6b8f..1282723e4f98a91f9954071fe7bbef27641dd042 100644
--- a/ui/base/dragdrop/gtk_dnd_util.cc
+++ b/ui/base/dragdrop/gtk_dnd_util.cc
@@ -55,6 +55,11 @@ void AddTargetToList(GtkTargetList* targets, int target_code) {
           ui::GetAtomForTarget(ui::CUSTOM_DATA), 0, ui::CUSTOM_DATA);
       break;
 
+    case ui::RENDERER_TAINT:
+      gtk_target_list_add(targets,
+          ui::GetAtomForTarget(ui::RENDERER_TAINT), 0, ui::RENDERER_TAINT);
+      break;
+
     default:
       NOTREACHED() << " Unexpected target code: " << target_code;
   }
@@ -114,6 +119,11 @@ GdkAtom GetAtomForTarget(int target) {
           kMimeTypeWebCustomData, false);
       return kCustomData;
 
+    case RENDERER_TAINT:
+      static const GdkAtom kRendererTaint = gdk_atom_intern(
+          "chromium/x-renderer-taint", false);
+      return kRendererTaint;
+
     default:
       NOTREACHED();
   }