[turbofan] Add the StackSlot operator to turbofan.

test/cctest/compiler/codegen-tester.h

Index: test/cctest/compiler/codegen-tester.h
diff --git a/test/cctest/compiler/codegen-tester.h b/test/cctest/compiler/codegen-tester.h
index df445fb9acda38d97cd5a4ad7b5bd8e21aa0420e..9af135e06748caba0e72b74ef133a5cb494e3d11 100644
--- a/test/cctest/compiler/codegen-tester.h
+++ b/test/cctest/compiler/codegen-tester.h
@@ -96,7 +96,6 @@ class BufferedRawMachineAssemblerTester
     return parameter_nodes_[index];
   }
 
-
   // The BufferedRawMachineAssemblerTester adds a Store node to the IR graph
   // to store the graph's return value in memory. The memory address for the
   // Store node is provided as a parameter. By storing the return value in
@@ -245,7 +244,6 @@ class BufferedRawMachineAssemblerTester<void>
                               : Load(p3, RawMachineAssembler::Parameter(3));
   }
 
-
   // The BufferedRawMachineAssemblerTester does not pass parameters directly
   // to the constructed IR graph. Instead it passes a pointer to the parameter
   // to the IR graph, and adds Load nodes to the IR graph to load the