Keep zone cached in SnapshotReader to allow removing ZoneHandle(Isolate*) interface.

runtime/lib/function.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/bootstrap_natives.h"
 
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
 #include "vm/exceptions.h"
 #include "vm/native_entry.h"
@@ skipping 12 matching lines @@
       Object::Handle(DartEntry::InvokeClosure(fun_arguments, fun_args_desc));
   if (result.IsError()) {
     Exceptions::PropagateError(Error::Cast(result));
   }
   return result.raw();
 }
 
 
 DEFINE_NATIVE_ENTRY(FunctionImpl_equals, 2) {
   const Instance& receiver = Instance::CheckedHandle(
-      isolate, arguments->NativeArgAt(0));
+      zone, arguments->NativeArgAt(0));
   ASSERT(receiver.IsClosure());
   GET_NATIVE_ARGUMENT(Instance, other, arguments->NativeArgAt(1));
   ASSERT(!other.IsNull());
   if (receiver.raw() == other.raw()) return Bool::True().raw();
   if (other.IsClosure()) {
     const Function& func_a = Function::Handle(Closure::function(receiver));
     const Function& func_b = Function::Handle(Closure::function(other));
     if (func_a.raw() == func_b.raw()) {
       ASSERT(!func_a.IsImplicitStaticClosureFunction());
       if (func_a.IsImplicitInstanceClosureFunction()) {
         const Context& context_a = Context::Handle(Closure::context(receiver));
         const Context& context_b = Context::Handle(Closure::context(other));
         const Object& receiver_a = Object::Handle(context_a.At(0));
         const Object& receiver_b = Object::Handle(context_b.At(0));
         if (receiver_a.raw() == receiver_b.raw()) return Bool::True().raw();
       }
     }
   }
   return Bool::False().raw();
 }
 
 
 DEFINE_NATIVE_ENTRY(FunctionImpl_hashCode, 1) {
   const Instance& receiver = Instance::CheckedHandle(
-      isolate, arguments->NativeArgAt(0));
+      zone, arguments->NativeArgAt(0));
   if (receiver.IsClosure()) {
     const Function& func = Function::Handle(Closure::function(receiver));
     // Hash together name, class name and signature.
     const Class& cls = Class::Handle(func.Owner());
     intptr_t result = String::Handle(func.name()).Hash();
     result += String::Handle(func.Signature()).Hash();
     result += String::Handle(cls.Name()).Hash();
     // Finalize hash value like for strings so that it fits into a smi.
     result += result << 3;
     result ^= result >> 11;
     result += result << 15;
     result &= ((static_cast<intptr_t>(1) << String::kHashBits) - 1);
     return Smi::New(result);
   }
   UNREACHABLE();
   return Object::null();
 }
 
 
 DEFINE_NATIVE_ENTRY(FunctionImpl_clone, 1) {
   const Instance& receiver = Instance::CheckedHandle(
-      isolate, arguments->NativeArgAt(0));
+      zone, arguments->NativeArgAt(0));
   ASSERT(receiver.IsClosure());
   if (receiver.IsClosure()) {
     const Function& func =
-        Function::Handle(isolate, Closure::function(receiver));
+        Function::Handle(zone, Closure::function(receiver));
     const Context& ctx =
-        Context::Handle(isolate, Closure::context(receiver));
+        Context::Handle(zone, Closure::context(receiver));
     Context& cloned_ctx =
-        Context::Handle(isolate, Context::New(ctx.num_variables()));
-    cloned_ctx.set_parent(Context::Handle(isolate, ctx.parent()));
-    Object& inst = Object::Handle(isolate);
+        Context::Handle(zone, Context::New(ctx.num_variables()));
+    cloned_ctx.set_parent(Context::Handle(zone, ctx.parent()));
+    Object& inst = Object::Handle(zone);
     for (int i = 0; i < ctx.num_variables(); i++) {
       inst = ctx.At(i);
       cloned_ctx.SetAt(i, inst);
     }
     return Closure::New(func, cloned_ctx);
   }
   return Object::null();
 }
 
 
 }  // namespace dart