Move CompilerStats from isolate to thread. Aggregate stats.

runtime/vm/isolate.h

 // Copyright (c) 2013, 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.
 
 #ifndef VM_ISOLATE_H_
 #define VM_ISOLATE_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/atomic.h"
@@ skipping 400 matching lines @@
     return defer_finalization_count_--;
   }
 
   bool AllowClassFinalization() {
     ASSERT(defer_finalization_count_ >= 0);
     return defer_finalization_count_ == 0;
   }
 
   void PrintJSON(JSONStream* stream, bool ref = true);
 
-  CompilerStats* compiler_stats() {
-    return compiler_stats_;
+  // Mutator thread is used to aggregate compiler stats.
+  CompilerStats* aggregate_compiler_stats() {
+    ASSERT(HasMutatorThread());
+    return mutator_thread_->compiler_stats();
   }
 
   VMTagCounters* vm_tag_counters() {
     return &vm_tag_counters_;
   }
 
   uword user_tag() const {
     return user_tag_;
   }
   static intptr_t user_tag_offset() {
@@ skipping 231 matching lines @@
   Mutex* type_canonicalization_mutex_;  // Protects type canonicalization.
   Mutex* constant_canonicalization_mutex_;  // Protects const canonicalization.
   MessageHandler* message_handler_;
   IsolateSpawnState* spawn_state_;
   bool is_runnable_;
   Dart_GcPrologueCallback gc_prologue_callback_;
   Dart_GcEpilogueCallback gc_epilogue_callback_;
   intptr_t defer_finalization_count_;
   DeoptContext* deopt_context_;
 
-  CompilerStats* compiler_stats_;
-
   bool is_service_isolate_;
 
   // Isolate-specific flags.
   NOT_IN_PRODUCT(
     bool type_checks_;
     bool asserts_;
     bool error_on_bad_type_;
     bool error_on_bad_override_;
   )
 
@@ skipping 225 matching lines @@
   intptr_t* spawn_count_;
 
   Dart_IsolateFlags isolate_flags_;
   bool paused_;
   bool errors_are_fatal_;
 };
 
 }  // namespace dart
 
 #endif  // VM_ISOLATE_H_