Support spawnUri in app snapshots.

runtime/vm/dart_api_impl.cc

 // 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.
 
 #include "include/dart_api.h"
 #include "include/dart_mirrors_api.h"
 #include "include/dart_native_api.h"
 
 #include "platform/assert.h"
 #include "lib/stacktrace.h"
@@ skipping 1563 matching lines @@
 #if defined(DEBUG)
   I->heap()->CollectAllGarbage();
   CheckFunctionTypesVisitor check_canonical(T);
   I->heap()->IterateObjects(&check_canonical);
 #endif  // #if defined(DEBUG)
 
   FullSnapshotWriter writer(Snapshot::kCore, vm_isolate_snapshot_buffer,
                             isolate_snapshot_buffer, ApiReallocate,
                             NULL /* instructions_writer */);
   writer.WriteFullSnapshot();
-  *vm_isolate_snapshot_size = writer.VmIsolateSnapshotSize();
+  if (vm_isolate_snapshot_buffer != NULL) {
+    *vm_isolate_snapshot_size = writer.VmIsolateSnapshotSize();
+  }
   *isolate_snapshot_size = writer.IsolateSnapshotSize();
   return Api::Success();
 }
 
 
 DART_EXPORT Dart_Handle Dart_CreateScriptSnapshot(uint8_t** buffer,
                                                   intptr_t* size) {
   API_TIMELINE_DURATION;
   DARTSCOPE(Thread::Current());
   Isolate* I = T->isolate();
@@ skipping 5196 matching lines @@
 }
 
 
 DART_EXPORT void Dart_DumpNativeStackTrace(void* context) {
 #ifndef PRODUCT
   Profiler::DumpStackTrace(context);
 #endif
 }
 
 }  // namespace dart