Move compiler cctests into v8::internal::compiler namespace.

test/cctest/compiler/test-run-stackcheck.cc

 // Copyright 2014 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.
 
 // TODO(jochen): Remove this after the setting is turned on globally.
 #define V8_IMMINENT_DEPRECATION_WARNINGS
 
 #include "test/cctest/compiler/function-tester.h"
 
-using namespace v8::internal;
-using namespace v8::internal::compiler;
+namespace v8 {
+namespace internal {
+namespace compiler {
 
 TEST(TerminateAtMethodEntry) {
   FunctionTester T("(function(a,b) { return 23; })");
 
   T.CheckCall(T.Val(23));
   T.isolate->stack_guard()->RequestTerminateExecution();
   T.CheckThrows(T.undefined(), T.undefined());
 }
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8