Revert "[compiler] Ship Ignition for all TurboFan code."

src/compiler-dispatcher/compiler-dispatcher-job.cc

 // 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-dispatcher/compiler-dispatcher-job.h"
 
 #include "src/assert-scope.h"
 #include "src/compilation-info.h"
 #include "src/compiler-dispatcher/compiler-dispatcher-tracer.h"
 #include "src/compiler.h"
@@ skipping 133 matching lines @@
 
     parse_info_->set_script(script);
     Handle<ScopeInfo> outer_scope_info(
         handle(ScopeInfo::cast(shared_->outer_scope_info())));
     if (outer_scope_info->length() > 0) {
       parse_info_->set_outer_scope_info(outer_scope_info);
     }
     parse_info_->set_shared_info(shared_);
 
     {
-      // Create a canonical handle scope for compiling Ignition bytecode. This
-      // is required by the constant array builder to de-duplicate objects
-      // without dereferencing handles.
-      CanonicalHandleScope canonical(isolate_);
+      // Create a canonical handle scope if compiling ignition bytecode. This is
+      // required by the constant array builder to de-duplicate objects without
+      // dereferencing handles.
+      std::unique_ptr<CanonicalHandleScope> canonical;
+      if (FLAG_ignition) canonical.reset(new CanonicalHandleScope(isolate_));
 
       // Do the parsing tasks which need to be done on the main thread. This
       // will also handle parse errors.
       parser_->Internalize(isolate_, script, parse_info_->literal() == nullptr);
     }
     parser_->HandleSourceURLComments(isolate_, script);
 
     parse_info_->set_character_stream(nullptr);
     parse_info_->set_unicode_cache(nullptr);
     parser_.reset();
@@ skipping 90 matching lines @@
   if (!source_.is_null()) {
     i::GlobalHandles::Destroy(Handle<Object>::cast(source_).location());
     source_ = Handle<String>::null();
   }
 
   status_ = CompileJobStatus::kInitial;
 }
 
 }  // namespace internal
 }  // namespace v8