Make sure that the d8 shell calls OnExit in case of exceptions.

src/d8.cc

Index: src/d8.cc
===================================================================
--- src/d8.cc	(revision 1547)
+++ src/d8.cc	(working copy)
@@ -586,8 +586,10 @@
         v8::HandleScope handle_scope;
         v8::Handle<v8::String> file_name = v8::String::New("unnamed");
         v8::Handle<v8::String> source = v8::String::New(argv[i + 1]);
-        if (!ExecuteString(source, file_name, false, true))
+        if (!ExecuteString(source, file_name, false, true)) {
+          OnExit();
           return 1;
+        }
         i++;
       } else if (strcmp(str, "-p") == 0 && i + 1 < argc) {
         int size = 0;
@@ -607,8 +609,10 @@
           printf("Error reading '%s'\n", str);
           return 1;
         }
-        if (!ExecuteString(source, file_name, false, true))
+        if (!ExecuteString(source, file_name, false, true)) {
+          OnExit();
           return 1;
+        }
       }
     }