Avoid allocating an exception object in the snapshot reader.

runtime/vm/snapshot.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_SNAPSHOT_H_
 #define VM_SNAPSHOT_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/bitfield.h"
@@ skipping 49 matching lines @@
 class RawCapability;
 class RawReceivePort;
 class RawSendPort;
 class RawStacktrace;
 class RawTokenStream;
 class RawType;
 class RawTypeRef;
 class RawTypeParameter;
 class RawTypeArguments;
 class RawTwoByteString;
+class RawUnhandledException;
 class RawUnresolvedClass;
 class String;
 class TokenStream;
 class TypeArguments;
 class UnhandledException;
 
 // Serialized object header encoding is as follows:
 // - Smi: the Smi value is written as is (last bit is not tagged).
 // - VM object (from VM isolate): (object id in vm isolate | 0x3)
 //   This valus is serialized as a negative number.
@@ skipping 161 matching lines @@
   ObjectStore* object_store() const { return isolate_->object_store(); }
   ClassTable* class_table() const { return isolate_->class_table(); }
   Object* ObjectHandle() { return &obj_; }
   Array* ArrayHandle() { return &array_; }
   String* StringHandle() { return &str_; }
   AbstractType* TypeHandle() { return &type_; }
   TypeArguments* TypeArgumentsHandle() { return &type_arguments_; }
   Array* TokensHandle() { return &tokens_; }
   TokenStream* StreamHandle() { return &stream_; }
   ExternalTypedData* DataHandle() { return &data_; }
-  UnhandledException* ErrorHandle() { return &error_; }
 
   // Reads an object.
   RawObject* ReadObject();
 
   // Add object to backward references.
   void AddBackRef(intptr_t id, Object* obj, DeserializeState state);
 
   // Get an object from the backward references list.
   Object* GetBackRef(intptr_t id);
 
@@ skipping 30 matching lines @@
   RawLibraryPrefix* NewLibraryPrefix();
   RawNamespace* NewNamespace();
   RawScript* NewScript();
   RawLiteralToken* NewLiteralToken();
   RawGrowableObjectArray* NewGrowableObjectArray();
   RawFloat32x4* NewFloat32x4(float v0, float v1, float v2, float v3);
   RawInt32x4* NewInt32x4(uint32_t v0, uint32_t v1, uint32_t v2, uint32_t v3);
   RawFloat64x2* NewFloat64x2(double v0, double v1);
   RawApiError* NewApiError();
   RawLanguageError* NewLanguageError();
+  RawUnhandledException* NewUnhandledException();
   RawObject* NewInteger(int64_t value);
   RawStacktrace* NewStacktrace();
 
  private:
   class BackRefNode : public ValueObject {
    public:
     BackRefNode(Object* reference, DeserializeState state)
         : reference_(reference), state_(state) {}
     Object* reference() const { return reference_; }
     bool is_deserialized() const { return state_ == kIsDeserialized; }
@@ skipping 70 matching lines @@
   friend class LiteralToken;
   friend class PatchClass;
   friend class Script;
   friend class Stacktrace;
   friend class TokenStream;
   friend class Type;
   friend class TypeArguments;
   friend class TypeParameter;
   friend class TypeRef;
   friend class UnresolvedClass;
+  friend class UnhandledException;
   friend class WeakProperty;
   friend class MirrorReference;
   DISALLOW_COPY_AND_ASSIGN(SnapshotReader);
 };
 
 
 class BaseWriter {
  public:
   // Size of the snapshot.
   intptr_t BytesWritten() const { return stream_.bytes_written(); }
@@ skipping 296 matching lines @@
  private:
   SnapshotWriter* writer_;
   bool as_references_;
 
   DISALLOW_COPY_AND_ASSIGN(SnapshotWriterVisitor);
 };
 
 }  // namespace dart
 
 #endif  // VM_SNAPSHOT_H_