Refactor VMTagScope to Thread* rather than Isolate*.

runtime/vm/compiler.cc

 // Copyright (c) 2012, 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.
 
 #include "vm/compiler.h"
 
 #include "vm/assembler.h"
 
 #include "vm/ast_printer.h"
 #include "vm/block_scheduler.h"
@@ skipping 270 matching lines @@
       return Error::null();
     } else {
       Isolate* isolate = Isolate::Current();
       Error& error = Error::Handle(isolate);
       error = isolate->object_store()->sticky_error();
       isolate->object_store()->clear_sticky_error();
       return error.raw();
     }
   }
 
-  Isolate* const isolate = Isolate::Current();
+  Thread* const thread = Thread::Current();
+  Isolate* const isolate = thread->isolate();
   // We remember all the classes that are being compiled in these lists. This
   // also allows us to reset the marked_for_parsing state in case we see an
   // error.
-  VMTagScope tagScope(isolate, VMTag::kCompileClassTagId);
+  VMTagScope tagScope(thread, VMTag::kCompileClassTagId);
   Class& parse_class = Class::Handle(isolate);
   const GrowableObjectArray& parse_list =
       GrowableObjectArray::Handle(isolate, GrowableObjectArray::New(4));
   const GrowableObjectArray& patch_list =
       GrowableObjectArray::Handle(isolate, GrowableObjectArray::New(4));
 
   // Parse the class and all the interfaces it implements and super classes.
   LongJumpScope jump;
   if (setjmp(*jump.Set()) == 0) {
-    StackZone zone(isolate);
+    StackZone zone(thread);
     if (FLAG_trace_compiler) {
       ISL_Print("Compiling Class %s '%s'\n", "", cls.ToCString());
     }
 
     // Add the primary class which needs to be parsed to the parse list.
     // Mark the class as parsed so that we don't recursively add the same
     // class back into the list.
     parse_list.Add(cls);
     cls.set_is_marked_for_parsing();
 
@@ skipping 44 matching lines @@
       if (parse_class.is_marked_for_parsing()) {
         parse_class.reset_is_marked_for_parsing();
       }
     }
     for (intptr_t i = 0; i < patch_list.Length(); i++) {
       parse_class ^= patch_list.At(i);
       if (parse_class.is_marked_for_parsing()) {
         parse_class.reset_is_marked_for_parsing();
       }
     }
+    Thread* const thread = Thread::Current();
     Isolate* const isolate = Isolate::Current();
-    StackZone zone(isolate);
+    StackZone zone(thread);
     Error& error = Error::Handle(isolate);
     error = isolate->object_store()->sticky_error();
     isolate->object_store()->clear_sticky_error();
     return error.raw();
   }
   UNREACHABLE();
   return Error::null();
 }
 
 
@@ skipping 719 matching lines @@
     return error.raw();
   }
   UNREACHABLE();
   return Error::null();
 }
 
 
 RawError* Compiler::CompileFunction(Thread* thread,
                                     const Function& function) {
   Isolate* isolate = thread->isolate();
-  VMTagScope tagScope(isolate, VMTag::kCompileUnoptimizedTagId);
+  VMTagScope tagScope(thread, VMTag::kCompileUnoptimizedTagId);
   TIMELINE_FUNCTION_COMPILATION_DURATION(isolate, "Function", function);
 
   if (!isolate->compilation_allowed()) {
     FATAL3("Precompilation missed function %s (%" Pd ", %s)\n",
            function.ToLibNamePrefixedQualifiedCString(),
            function.token_pos(),
            Function::KindToCString(function.kind()));
   }
 
   CompilationPipeline* pipeline =
@@ skipping 34 matching lines @@
     ISL_Print("Ensure unoptimized code for %s\n", function.ToCString());
   }
   return Error::null();
 }
 
 
 RawError* Compiler::CompileOptimizedFunction(Thread* thread,
                                              const Function& function,
                                              intptr_t osr_id) {
   Isolate* isolate = thread->isolate();
-  VMTagScope tagScope(isolate, VMTag::kCompileOptimizedTagId);
+  VMTagScope tagScope(thread, VMTag::kCompileOptimizedTagId);
   TIMELINE_FUNCTION_COMPILATION_DURATION(isolate,
                                          "OptimizedFunction", function);
 
   CompilationPipeline* pipeline =
       CompilationPipeline::New(thread->zone(), function);
   return CompileFunctionHelper(pipeline, function, true, osr_id);
 }
 
 
 // This is only used from unit tests.
@@ skipping 237 matching lines @@
     const Object& result =
       PassiveObject::Handle(isolate->object_store()->sticky_error());
     isolate->object_store()->clear_sticky_error();
     return result.raw();
   }
   UNREACHABLE();
   return Object::null();
 }
 
 }  // namespace dart