Add RPC and UI for reachable size of an object / all instances of a class.

runtime/vm/raw_object.h

 // 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.
 
 #ifndef VM_RAW_OBJECT_H_
 #define VM_RAW_OBJECT_H_
 
 #include "platform/assert.h"
 #include "vm/atomic.h"
 #include "vm/globals.h"
@@ skipping 596 matching lines @@
   friend class Object;
   friend class OneByteString;  // StoreSmi
   friend class RawCode;
   friend class RawExternalTypedData;
   friend class RawInstructions;
   friend class RawInstance;
   friend class RawTypedData;
   friend class Scavenger;
   friend class ScavengerVisitor;
   friend class SizeExcludingClassVisitor;  // GetClassId
+  friend class InstanceAccumulator;  // GetClassId
   friend class RetainingPathVisitor;  // GetClassId
   friend class SkippedCodeFunctions;  // StorePointer
   friend class InstructionsReader;  // tags_ check
   friend class InstructionsWriter;
   friend class SnapshotReader;
   friend class SnapshotWriter;
   friend class String;
   friend class TypedData;
   friend class TypedDataView;
   friend class WeakProperty;  // StorePointer
@@ skipping 1639 matching lines @@
   COMPILE_ASSERT(kExternalTypedDataInt8ArrayCid ==
                  kTypedDataInt8ArrayViewCid + 15);
   COMPILE_ASSERT(kByteBufferCid == kExternalTypedDataInt8ArrayCid + 14);
   COMPILE_ASSERT(kNullCid == kByteBufferCid + 1);
   return (kNullCid - kTypedDataInt8ArrayCid);
 }
 
 }  // namespace dart
 
 #endif  // VM_RAW_OBJECT_H_