Introduce Dart_SetVMFlags API function.

runtime/vm/dart_api_impl.cc

Index: runtime/vm/dart_api_impl.cc
===================================================================
--- runtime/vm/dart_api_impl.cc	(revision 1859)
+++ runtime/vm/dart_api_impl.cc	(working copy)
@@ -463,12 +463,13 @@
 
 
 // TODO(iposva): This is a placeholder for the eventual external Dart API.
-DART_EXPORT bool Dart_Initialize(int argc,
-                                 const char** argv,
-                                 Dart_IsolateInitCallback callback) {
-  return Dart::InitOnce(argc, argv, callback);
+DART_EXPORT bool Dart_Initialize(Dart_IsolateInitCallback callback) {
+  return Dart::InitOnce(callback);
 }
 
+DART_EXPORT void Dart_SetVMFlags(int argc, const char** argv) {
+  Flags::ProcessCommandLineFlags(argc, argv);

[siva, 2011/11/29 19:08:43]

Currently we ensure that Dart_Initialize is called only once and hence
Flags::ProcessCommandLineFlags is also called only once.

In the new scheme it is possible to call Dart_SetVMFlags multiple times we
should protect against that and we should also ensure that Dart_SetVMFlags is
called before Dart_Initialize is called.

[podivilov, 2011/11/30 11:50:36]

Done.

+}
 
 DART_EXPORT bool Dart_IsVMFlagSet(const char* flag_name) {
   if (Flags::Lookup(flag_name) != NULL) {