[stubs] Reduce number of StoreTransitionStub instances.

src/ic/ppc/handler-compiler-ppc.cc

Index: src/ic/ppc/handler-compiler-ppc.cc
diff --git a/src/ic/ppc/handler-compiler-ppc.cc b/src/ic/ppc/handler-compiler-ppc.cc
index f9eb98d503e4e41891da56e5b5a0e1ee4e7fe8de..aafdc77c9b0824f11122926b1f78df8253a3f436 100644
--- a/src/ic/ppc/handler-compiler-ppc.cc
+++ b/src/ic/ppc/handler-compiler-ppc.cc
@@ -130,9 +130,13 @@ void PropertyHandlerCompiler::DiscardVectorAndSlot() {
   __ addi(sp, sp, Operand(2 * kPointerSize));
 }
 
-void PropertyHandlerCompiler::PushReturnAddress(Register tmp) { UNREACHABLE(); }
+void PropertyHandlerCompiler::PushReturnAddress(Register tmp) {
+  // No-op. Return address is in lr register.
+}
 
-void PropertyHandlerCompiler::PopReturnAddress(Register tmp) { UNREACHABLE(); }
+void PropertyHandlerCompiler::PopReturnAddress(Register tmp) {
+  // No-op. Return address is in lr register.
+}
 
 void PropertyHandlerCompiler::GenerateDictionaryNegativeLookup(
     MacroAssembler* masm, Label* miss_label, Register receiver,