Introduce API to trigger exception on JS execution.

test/cctest/test-api.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 22381 matching lines @@
   V8::RunMicrotasks(isolate);
   CHECK_EQ(3, global->Get(v8_str("x1"))->Int32Value());
   CHECK_EQ(4, global->Get(v8_str("x2"))->Int32Value());
 }
 
 
 TEST(DisallowJavascriptExecutionScope) {
   LocalContext context;
   v8::Isolate* isolate = context->GetIsolate();
   v8::HandleScope scope(isolate);
-  v8::Isolate::DisallowJavascriptExecutionScope no_js(isolate);
+  v8::Isolate::DisallowJavascriptExecutionScope no_js(
+      isolate, v8::Isolate::DisallowJavascriptExecutionScope::CRASH_ON_FAILURE);
   CompileRun("2+2");
 }
 
 
 TEST(AllowJavascriptExecutionScope) {
   LocalContext context;
   v8::Isolate* isolate = context->GetIsolate();
   v8::HandleScope scope(isolate);
-  v8::Isolate::DisallowJavascriptExecutionScope no_js(isolate);
+  v8::Isolate::DisallowJavascriptExecutionScope no_js(
+      isolate, v8::Isolate::DisallowJavascriptExecutionScope::CRASH_ON_FAILURE);
+  v8::Isolate::DisallowJavascriptExecutionScope throw_js(
+      isolate, v8::Isolate::DisallowJavascriptExecutionScope::THROW_ON_FAILURE);
   { v8::Isolate::AllowJavascriptExecutionScope yes_js(isolate);
     CompileRun("1+1");
   }
 }
+
+
+TEST(ThrowOnJavascriptExecution) {
+  LocalContext context;
+  v8::Isolate* isolate = context->GetIsolate();
+  v8::HandleScope scope(isolate);
+  v8::TryCatch try_catch;
+  v8::Isolate::DisallowJavascriptExecutionScope throw_js(
+      isolate, v8::Isolate::DisallowJavascriptExecutionScope::THROW_ON_FAILURE);
+  CompileRun("1+1");
+  CHECK(try_catch.HasCaught());
+}