Cleanup app snapshots on isolate/vm exit.

runtime/bin/gen_snapshot.cc

Index: runtime/bin/gen_snapshot.cc
diff --git a/runtime/bin/gen_snapshot.cc b/runtime/bin/gen_snapshot.cc
index 732493d5fe11dd42cf3c9cdf7dad25252f531a6f..93227bbe76a0d640a7f3891647ff910f567d8bc2 100644
--- a/runtime/bin/gen_snapshot.cc
+++ b/runtime/bin/gen_snapshot.cc
@@ -1148,7 +1148,7 @@ static Dart_Isolate CreateServiceIsolate(const char* script_uri,
                                          void* data,
                                          char** error) {
   IsolateData* isolate_data =
-      new IsolateData(script_uri, package_root, package_config);
+      new IsolateData(script_uri, package_root, package_config, NULL);
   Dart_Isolate isolate = NULL;
   isolate = Dart_CreateIsolate(script_uri, main, NULL, NULL, NULL, isolate_data,
                                error);
@@ -1252,7 +1252,7 @@ int main(int argc, char** argv) {
   }
 
   IsolateData* isolate_data = new IsolateData(NULL, commandline_package_root,
-                                              commandline_packages_file);
+                                              commandline_packages_file, NULL);
   Dart_Isolate isolate =
       Dart_CreateIsolate(NULL, NULL, NULL, NULL, NULL, isolate_data, &error);
   if (isolate == NULL) {
@@ -1300,7 +1300,7 @@ int main(int argc, char** argv) {
 
     // Now we create an isolate into which we load all the code that needs to
     // be in the snapshot.
-    isolate_data = new IsolateData(NULL, NULL, NULL);
+    isolate_data = new IsolateData(NULL, NULL, NULL, NULL);
     const uint8_t* kernel = NULL;
     intptr_t kernel_length = 0;
     const bool is_kernel_file =