VM: Fix more places with isolate embedded into unoptimized code.

runtime/vm/stub_code_x64.cc

Index: runtime/vm/stub_code_x64.cc
diff --git a/runtime/vm/stub_code_x64.cc b/runtime/vm/stub_code_x64.cc
index 82a198aefae3ce91ee590dc34039be800146943d..ea7baa4f5be80e51ce1c968a04944941cc439e11 100644
--- a/runtime/vm/stub_code_x64.cc
+++ b/runtime/vm/stub_code_x64.cc
@@ -2031,11 +2031,9 @@ DECLARE_LEAF_RUNTIME_ENTRY(intptr_t,
 // Return ZF set.
 // Note: A Mint cannot contain a value that would fit in Smi, a Bigint
 // cannot contain a value that fits in Mint or Smi.
-void StubCode::GenerateIdenticalWithNumberCheckStub(Assembler* assembler,
-                                                    const Register left,
-                                                    const Register right,
-                                                    const Register unused1,
-                                                    const Register unused2) {
+static void GenerateIdenticalWithNumberCheckStub(Assembler* assembler,
+                                                 const Register left,
+                                                 const Register right) {
   Label reference_compare, done, check_mint, check_bigint;
   // If any of the arguments is Smi do reference compare.
   __ testq(left, Immediate(kSmiTagMask));