Introduce VM API for the patching mechanism.

runtime/vm/dart_api_impl.cc

Index: runtime/vm/dart_api_impl.cc
diff --git a/runtime/vm/dart_api_impl.cc b/runtime/vm/dart_api_impl.cc
index f8c18ed05f9bb276ced8351b1aab8341465704a2..f1acf1c55617c9db862c4d8ac567aa2d93ac84bf 100644
--- a/runtime/vm/dart_api_impl.cc
+++ b/runtime/vm/dart_api_impl.cc
@@ -4422,6 +4422,34 @@ DART_EXPORT Dart_Handle Dart_LoadSource(Dart_Handle library,
 }
 
 
+DART_EXPORT Dart_Handle Dart_LoadPatch(Dart_Handle library,

[Mads Ager (google), 2012/10/25 10:47:46]

This code is completely duplicated from LoadSource. See patch set 1 for the code
where I have shared the implementation. The reason for duplicating here is the
macro that uses CURRENT_FUNC for the error message. 

+                                       Dart_Handle url,
+                                       Dart_Handle patch_source) {
+  TIMERSCOPE(time_script_loading);
+  Isolate* isolate = Isolate::Current();
+  DARTSCOPE(isolate);
+  if (FLAG_use_cha) {

[Ivan Posva, 2012/10/26 04:33:34]

Leave it like this but note: dartbug.com/6288

+    RemoveOptimizedCode();
+  }
+  const Library& lib = Api::UnwrapLibraryHandle(isolate, library);
+  if (lib.IsNull()) {
+    RETURN_TYPE_ERROR(isolate, library, Library);
+  }
+  const String& url_str = Api::UnwrapStringHandle(isolate, url);
+  if (url_str.IsNull()) {
+    RETURN_TYPE_ERROR(isolate, url, String);
+  }
+  const String& source_str = Api::UnwrapStringHandle(isolate, patch_source);
+  if (source_str.IsNull()) {
+    RETURN_TYPE_ERROR(isolate, patch_source, String);
+  }
+  Dart_Handle result;
+  CompileSource(isolate, lib, url_str, source_str,
+                RawScript::kPatchTag, &result);
+  return result;
+}
+
+
 DART_EXPORT Dart_Handle Dart_SetNativeResolver(
     Dart_Handle library,
     Dart_NativeEntryResolver resolver) {