Refactor the dart api a bit:

runtime/vm/snapshot_test.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/snapshot.h"
 
 #include "vm/assert.h"
 #include "vm/bigint_operations.h"
 #include "vm/class_finalizer.h"
 #include "vm/unit_test.h"
@@ skipping 307 matching lines @@
       "  final int fld2;\n"
       "  static int fld3;\n"
       "  static final int fld4 = 10;\n"
       "}\n"
       "class FieldsTest {\n"
       "  static Fields testMain() {\n"
       "    Fields obj = new Fields(10, 20);\n"
       "    return obj;\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   uint8_t* buffer;
 
   // Start an Isolate, load a script and create a full snapshot.
   Timer timer1(true, "Snapshot_test");
   timer1.Start();
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
@@ skipping 21 matching lines @@
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
     timer2.Stop();
     OS::PrintErr("From Snapshot: %dus\n", timer2.TotalElapsedTime());
 
     // Invoke a function which returns an object.
     result = Dart_InvokeStatic(TestCase::lib(),
                                Dart_NewString("FieldsTest"),
                                Dart_NewString("testMain"),
                                0,
                                NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
-    EXPECT(!Dart_ExceptionOccurred(retobj));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!Dart_ExceptionOccurred(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 
   free(buffer);
 }
 
 
 UNIT_TEST_CASE(FullSnapshot1) {
@@ skipping 20 matching lines @@
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
     ClassFinalizer::FinalizePendingClasses();
     timer1.Stop();
     OS::PrintErr("Without Snapshot: %dus\n", timer1.TotalElapsedTime());
 
     // Write snapshot with object content.
     SnapshotWriter writer(true, &buffer, &allocator);
     writer.WriteFullSnapshot();
 
     // Invoke a function which returns an object.
-    Dart_Result result = Dart_InvokeStatic(lib,
+    Dart_Handle result = Dart_InvokeStatic(lib,
                                Dart_NewString("FieldsTest"),
                                Dart_NewString("testMain"),
                                0,
                                NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
-    EXPECT(!Dart_ExceptionOccurred(retobj));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!Dart_ExceptionOccurred(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 
   // Now Create another isolate using the snapshot and execute a method
   // from the script.
   Timer timer2(true, "Snapshot_test");
   timer2.Start();
   Dart_CreateIsolate(buffer, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
     timer2.Stop();
     OS::PrintErr("From Snapshot: %dus\n", timer2.TotalElapsedTime());
 
     // Invoke a function which returns an object.
-    Dart_Result result = Dart_InvokeStatic(TestCase::lib(),
+    Dart_Handle result = Dart_InvokeStatic(TestCase::lib(),
                                Dart_NewString("FieldsTest"),
                                Dart_NewString("testMain"),
                                0,
                                NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
-    if (Dart_ExceptionOccurred(retobj)) {
+    EXPECT(Dart_IsValid(result));
+    if (Dart_ExceptionOccurred(result)) {
       // Print the exception object.
       fprintf(stderr, "An unhandled exception has been thrown\n");
-      Dart_Result exception_result = Dart_GetException(retobj);
-      assert(Dart_IsValidResult(exception_result));
-      Dart_Handle retval_string = Dart_GetResult(exception_result);
-      Dart_Result retstr = Dart_StringToCString(retval_string);
-      const char* obj_cstring = Dart_IsValidResult(retstr) ?
-          Dart_GetResultAsCString(retstr) : Dart_GetErrorCString(retstr);
+      Dart_Handle exception_result = Dart_GetException(result);
+      assert(Dart_IsValid(exception_result));
+      const char* obj_cstring = NULL;
+      Dart_Handle retstr = Dart_StringToCString(exception_result, &obj_cstring);
+      if (!Dart_IsValid(retstr)) {
+        obj_cstring = Dart_GetError(retstr);
+      }
       fprintf(stderr, "%s", obj_cstring);
     }
-    EXPECT(!Dart_ExceptionOccurred(retobj));
+    EXPECT(!Dart_ExceptionOccurred(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 
   free(buffer);
 }
 #endif  // TARGET_ARCH_IA32.
 
 }  // namespace dart