Make array allocation stub shared between isolates.

runtime/vm/debugger_ia32.cc

Index: runtime/vm/debugger_ia32.cc
diff --git a/runtime/vm/debugger_ia32.cc b/runtime/vm/debugger_ia32.cc
index 6b9ae72bc1fef0ed1998b919458444ca11c524b1..04c527c697be8b51231ca7508d66aa3d5ac8c954 100644
--- a/runtime/vm/debugger_ia32.cc
+++ b/runtime/vm/debugger_ia32.cc
@@ -26,7 +26,6 @@ void CodeBreakpoint::PatchCode() {
   ASSERT(!is_enabled_);
   const Code& code = Code::Handle(code_);
   const Instructions& instrs = Instructions::Handle(code.instructions());
-  Isolate* isolate = Isolate::Current();
   {
     WritableInstructionsScope writable(instrs.EntryPoint(), instrs.size());
     switch (breakpoint_kind_) {
@@ -34,13 +33,13 @@ void CodeBreakpoint::PatchCode() {
       case RawPcDescriptors::kUnoptStaticCall: {
         saved_value_ = CodePatcher::GetStaticCallTargetAt(pc_, code);
         CodePatcher::PatchStaticCallAt(
-            pc_, code, isolate->stub_code()->ICCallBreakpointEntryPoint());
+            pc_, code, StubCode::ICCallBreakpointEntryPoint());
         break;
       }
       case RawPcDescriptors::kRuntimeCall: {
         saved_value_ = CodePatcher::GetStaticCallTargetAt(pc_, code);
         CodePatcher::PatchStaticCallAt(
-            pc_, code, isolate->stub_code()->RuntimeCallBreakpointEntryPoint());
+            pc_, code, StubCode::RuntimeCallBreakpointEntryPoint());
         break;
       }
       default: