Revert of [refactoring] Split CodeAssemblerState out of CodeAssembler

test/cctest/compiler/code-assembler-tester.h

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "src/compiler/code-assembler.h"
 #include "src/handles.h"
 #include "src/interface-descriptors.h"
 #include "src/isolate.h"
 #include "test/cctest/compiler/function-tester.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
-class CodeAssemblerTester {
+class ZoneHolder {
  public:
-  // Test generating code for a stub. Assumes VoidDescriptor call interface.
-  explicit CodeAssemblerTester(Isolate* isolate)
-      : zone_(isolate->allocator(), ZONE_NAME),
-        scope_(isolate),
-        state_(isolate, &zone_, VoidDescriptor(isolate),
-               Code::ComputeFlags(Code::STUB), "test") {}
+  explicit ZoneHolder(Isolate* isolate)
+      : held_zone_(isolate->allocator(), ZONE_NAME) {}
+  Zone* held_zone() { return &held_zone_; }
+
+ private:
+  Zone held_zone_;
+};
+
+// Inherit from ZoneHolder in order to create a zone that can be passed to
+// CodeAssembler base class constructor.
+template <typename CodeAssemblerT>
+class CodeAssemblerTesterImpl : private ZoneHolder, public CodeAssemblerT {
+ public:
+  // Test generating code for a stub.
+  CodeAssemblerTesterImpl(Isolate* isolate,
+                          const CallInterfaceDescriptor& descriptor)
+      : ZoneHolder(isolate),
+        CodeAssemblerT(isolate, ZoneHolder::held_zone(), descriptor,
+                       Code::ComputeFlags(Code::STUB), "test"),
+        scope_(isolate) {}
 
   // Test generating code for a JS function (e.g. builtins).
-  CodeAssemblerTester(Isolate* isolate, int parameter_count,
-                      Code::Kind kind = Code::BUILTIN)
-      : zone_(isolate->allocator(), ZONE_NAME),
-        scope_(isolate),
-        state_(isolate, &zone_, parameter_count, Code::ComputeFlags(kind),
-               "test") {}
+  CodeAssemblerTesterImpl(Isolate* isolate, int parameter_count,
+                          Code::Kind kind = Code::BUILTIN)
+      : ZoneHolder(isolate),
+        CodeAssemblerT(isolate, ZoneHolder::held_zone(), parameter_count,
+                       Code::ComputeFlags(kind), "test"),
+        scope_(isolate) {}
 
   // This constructor is intended to be used for creating code objects with
   // specific flags.
-  CodeAssemblerTester(Isolate* isolate, Code::Flags flags)
-      : zone_(isolate->allocator(), ZONE_NAME),
-        scope_(isolate),
-        state_(isolate, &zone_, 0, flags, "test") {}
-
-  CodeAssemblerState* state() { return &state_; }
-
-  Handle<Code> GenerateCode() { return CodeAssembler::GenerateCode(&state_); }
+  CodeAssemblerTesterImpl(Isolate* isolate, Code::Flags flags)
+      : ZoneHolder(isolate),
+        CodeAssemblerT(isolate, ZoneHolder::held_zone(), 0, flags, "test"),
+        scope_(isolate) {}
 
   Handle<Code> GenerateCodeCloseAndEscape() {
-    return scope_.CloseAndEscape(CodeAssembler::GenerateCode(&state_));
+    return scope_.CloseAndEscape(CodeAssemblerT::GenerateCode());
   }
 
  private:
-  Zone zone_;
   HandleScope scope_;
   LocalContext context_;
-  CodeAssemblerState state_;
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8