Lazily format LanguageError messages (fix issue 15069).

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/globals.h"
 #include "vm/token.h"
@@ skipping 1074 matching lines @@
   RawObject** to() {
     return reinterpret_cast<RawObject**>(&ptr()->message_);
   }
 };
 
 
 class RawLanguageError : public RawError {
   RAW_HEAP_OBJECT_IMPLEMENTATION(LanguageError);
 
   RawObject** from() {
-    return reinterpret_cast<RawObject**>(&ptr()->message_);
+    return reinterpret_cast<RawObject**>(&ptr()->previous_error_);
   }
+  RawError* previous_error_;  // May be null.
+  RawScript* script_;
   RawString* message_;
+  RawString* formatted_message_;  // Incl. previous error's formatted message.
   RawObject** to() {
-    return reinterpret_cast<RawObject**>(&ptr()->message_);
+    return reinterpret_cast<RawObject**>(&ptr()->formatted_message_);
   }
+  intptr_t token_pos_;  // Source position in script_.
+  int8_t kind_;  // Of type LanguageError::Kind.
 };
 
 
 class RawUnhandledException : public RawError {
   RAW_HEAP_OBJECT_IMPLEMENTATION(UnhandledException);
 
   RawObject** from() {
     return reinterpret_cast<RawObject**>(&ptr()->exception_);
   }
   RawInstance* exception_;
@@ skipping 609 matching lines @@
   // Make sure this is updated when new TypedData types are added.
   ASSERT(kTypedDataInt8ArrayViewCid == kTypedDataInt8ArrayCid + 13);
   ASSERT(kExternalTypedDataInt8ArrayCid == kTypedDataInt8ArrayViewCid + 14);
   ASSERT(kNullCid == kExternalTypedDataInt8ArrayCid + 13);
   return (kNullCid - kTypedDataInt8ArrayCid);
 }
 
 }  // namespace dart
 
 #endif  // VM_RAW_OBJECT_H_