ported from UXP: Issue #2112 - Part 9: Remove handling for multiple style backends (b96b733b)

layout/base/PresShell.cpp

@@ -36,7 +36,6 @@
 #include "mozilla/TouchEvents.h"
 #include "mozilla/UniquePtr.h"
 #include "mozilla/Unused.h"
-#include "mozilla/StyleBackendType.h"
 #include <algorithm>
 
 #ifdef XP_WIN
@@ -872,8 +871,7 @@ PresShell::Init(nsIDocument* aDocument,
 
   // Bind the context to the presentation shell.
   mPresContext = aPresContext;
-  StyleBackendType backend = StyleBackendType::Gecko;
-  aPresContext->AttachShell(this, backend);
+  aPresContext->AttachShell(this);
 
   // Now we can initialize the style set. Make sure to set the member before
   // calling Init, since various subroutines need to find the style set off