Switch GetConcurrentlyOptimizedCode to MaybeHandle.

src/optimizing-compile-dispatcher.cc

 // Copyright 2012 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/optimizing-compile-dispatcher.h"
 
 #include "src/base/atomicops.h"
 #include "src/full-codegen/full-codegen.h"
 #include "src/isolate.h"
 #include "src/v8.h"
@@ skipping 226 matching lines @@
       BackEdgeTable::RemoveStackCheck(code, offset);
     } else {
       if (function->IsOptimized()) {
         if (FLAG_trace_concurrent_recompilation) {
           PrintF("  ** Aborting compilation for ");
           function->ShortPrint();
           PrintF(" as it has already been optimized.\n");
         }
         DisposeOptimizedCompileJob(job, false);
       } else {
-        Handle<Code> code = Compiler::GetConcurrentlyOptimizedCode(job);
+        MaybeHandle<Code> code = Compiler::GetConcurrentlyOptimizedCode(job);
         function->ReplaceCode(code.is_null() ? function->shared()->code()
-                                             : *code);
+                                             : *code.ToHandleChecked());
       }
     }
   }
 }
 
 
 void OptimizingCompileDispatcher::QueueForOptimization(
     OptimizedCompileJob* job) {
   DCHECK(IsQueueAvailable());
   CompilationInfo* info = job->info();
@@ skipping 89 matching lines @@
       info->closure()->PrintName();
       PrintF(", AST id %d]\n", info->osr_ast_id().ToInt());
     }
     DisposeOptimizedCompileJob(stale, false);
   }
   osr_buffer_[osr_buffer_cursor_] = job;
   osr_buffer_cursor_ = (osr_buffer_cursor_ + 1) % osr_buffer_capacity_;
 }
 }  // namespace internal
 }  // namespace v8