VM: Use constant pool also for leaf runtime calls on x64, arm, arm64 and mips.

runtime/vm/stub_code_x64_test.cc

Index: runtime/vm/stub_code_x64_test.cc
diff --git a/runtime/vm/stub_code_x64_test.cc b/runtime/vm/stub_code_x64_test.cc
index 987daf4b172ce710db9527612f359e146d9ff457..d3b94dcc0f679bde0e5862080d2bfd920be2e09f 100644
--- a/runtime/vm/stub_code_x64_test.cc
+++ b/runtime/vm/stub_code_x64_test.cc
@@ -76,12 +76,12 @@ static void GenerateCallToCallLeafRuntimeStub(Assembler* assembler,
                                               int value2) {
   const Smi& smi1 = Smi::ZoneHandle(Smi::New(value1));
   const Smi& smi2 = Smi::ZoneHandle(Smi::New(value2));
-  __ enter(Immediate(0));
+  __ EnterStubFrame();
   __ ReserveAlignedFrameSpace(0);
   __ LoadObject(CallingConventions::kArg1Reg, smi1);
   __ LoadObject(CallingConventions::kArg2Reg, smi2);
   __ CallRuntime(kTestLeafSmiAddRuntimeEntry, 2);  // Call SmiAdd runtime func.
-  __ leave();
+  __ LeaveStubFrame();
   __ ret();  // Return value is in RAX.
 }