Add test that passes invalid arguments to socket methods and fix

runtime/bin/process.cc

Index: runtime/bin/process.cc
diff --git a/runtime/bin/process.cc b/runtime/bin/process.cc
index e33ea613d9c6b99d669f7bf5fe4b1f173db54938..8c8a78288eb18b0ce8a5d371b2edf110dde0966e 100644
--- a/runtime/bin/process.cc
+++ b/runtime/bin/process.cc
@@ -96,6 +96,7 @@ void FUNCTION_NAME(Process_Start)(Dart_NativeArguments args) {
                            "Environment values must be builtin strings",
                            &environment_length);
     if (string_environment == NULL) {
+      delete[] string_args;
       Dart_SetReturnValue(args, Dart_NewBoolean(false));
       Dart_ExitScope();
       return;