Fix missing cases of empty_string canonicalization

src/ppc/macro-assembler-ppc.cc

Index: src/ppc/macro-assembler-ppc.cc
diff --git a/src/ppc/macro-assembler-ppc.cc b/src/ppc/macro-assembler-ppc.cc
index 4a5b181a837c0086a28d4f751b4632dc761c0f09..81f25c2dd705e11fed9123db6caa5952ba990ef6 100644
--- a/src/ppc/macro-assembler-ppc.cc
+++ b/src/ppc/macro-assembler-ppc.cc
@@ -1192,19 +1192,6 @@ void MacroAssembler::EnterExitFrame(bool save_doubles, int stack_space,
   StoreP(r8, MemOperand(fp, ExitFrameConstants::kSPOffset));
 }
 
-
-void MacroAssembler::InitializeNewString(Register string, Register length,
-                                         Heap::RootListIndex map_index,
-                                         Register scratch1, Register scratch2) {
-  SmiTag(scratch1, length);
-  LoadRoot(scratch2, map_index);
-  StoreP(scratch1, FieldMemOperand(string, String::kLengthOffset), r0);
-  li(scratch1, Operand(String::kEmptyHashField));
-  StoreP(scratch2, FieldMemOperand(string, HeapObject::kMapOffset), r0);
-  StoreP(scratch1, FieldMemOperand(string, String::kHashFieldSlot), r0);
-}
-
-
 int MacroAssembler::ActivationFrameAlignment() {
 #if !defined(USE_SIMULATOR)
   // Running on the real platform. Use the alignment as mandated by the local