Drop deprecated method for backing store from AccessBuilder.

src/compiler/access-builder.h

Index: src/compiler/access-builder.h
diff --git a/src/compiler/access-builder.h b/src/compiler/access-builder.h
index 7d0bda1398e7aaec383913b1096f5a22923aab3d..72dd0234aa071eb8030145c3dcc244d0b1a59d99 100644
--- a/src/compiler/access-builder.h
+++ b/src/compiler/access-builder.h
@@ -37,9 +37,6 @@ class AccessBuilder FINAL : public AllStatic {
   // Provides access to FixedArray elements.
   static ElementAccess ForFixedArrayElement();
 
-  // TODO(mstarzinger): Raw access only for testing, drop me.
-  static ElementAccess ForBackingStoreElement(MachineType rep);
-
   // Provides access to Fixed{type}TypedArray and External{type}Array elements.
   static ElementAccess ForTypedArrayElement(ExternalArrayType type,
                                             bool is_external);