Fix two deprecation warnings (#456)

* Fix deprecation warning, use Nan::TryCatch.

Fixes the following compiler warning:

    Release/obj.target/appmetrics/geni/appmetrics.cpp: In function 'void
    emitMessage(uv_async_t*, int)':
    Release/obj.target/appmetrics/geni/appmetrics.cpp:396:18: warning:
    'v8::TryCatch::TryCatch()' is deprecated: Use isolate version
    [-Wdeprecated-declarations]
             TryCatch try_catch;

* Fix deprecation warning, use Nan::CallAsFunction().

Fixes the following compiler warning:

    Release/obj.target/appmetrics/geni/appmetrics.cpp: In function
    'v8::Local<v8::Object> getRequireCache(v8::Local<v8::Object>)':
    Release/obj.target/appmetrics/geni/appmetrics.cpp:597:151: warning:
    'v8::Local<v8::Value>
    v8::Object::CallAsFunction(v8::Local<v8::Value>, int,
        v8::Local<v8::Value>*)' is deprecated: Use maybe version
    [-Wdeprecated-declarations]
         Local<Value> m =
         module->Get(Nan::New<String>("require").ToLocalChecked())->ToObject()->CallAsFunction(Nan::GetCurrentContext()->Global(),
             1, args);

Author: bnoordhuis

src/appmetrics.cpp

@@ -393,7 +393,7 @@ static void emitMessage(uv_async_t *handle, int status) {
     uv_mutex_unlock(messageListMutex);
 
     while(currentMessage != NULL ) {
-        TryCatch try_catch;
+        Nan::TryCatch try_catch;
         const unsigned argc = 2;
         Local<Value> argv[argc];
         const char * source = (*currentMessage->source).c_str();
@@ -404,11 +404,7 @@ static void emitMessage(uv_async_t *handle, int status) {
 
         listener->callback->Call(argc, argv);
         if (try_catch.HasCaught()) {
-#if NODE_VERSION_AT_LEAST(0, 11, 0) // > v0.11+
-            node::FatalException(v8::Isolate::GetCurrent(), try_catch);
-#else
-            node::FatalException(try_catch);
-#endif
+            Nan::FatalException(try_catch);
         }
         MessageData* nextMessage = currentMessage->next;
         freePayload(currentMessage);
@@ -594,9 +590,16 @@ void lrtime(const Nan::FunctionCallbackInfo<v8::Value>& info) {
 static Local<Object> getRequireCache(Local<Object> module) {
     Nan::EscapableHandleScope scope;
     Local<Value> args[] = { Nan::New<String>("module").ToLocalChecked() };
-    Local<Value> m = module->Get(Nan::New<String>("require").ToLocalChecked())->ToObject()->CallAsFunction(Nan::GetCurrentContext()->Global(), 1, args);
-    Local<Object> cache = m->ToObject()->Get(Nan::New<String>("_cache").ToLocalChecked())->ToObject();
-    return scope.Escape(cache);
+    Local<String> require_string = Nan::New<String>("require").ToLocalChecked();
+    Local<Value> require_v = Nan::Get(module, require_string).ToLocalChecked();
+    Local<Object> require_obj = Nan::To<Object>(require_v).ToLocalChecked();
+    Local<Object> global_obj = Nan::GetCurrentContext()->Global();
+    Local<Value> module_v = Nan::CallAsFunction(require_obj, global_obj, 1, args).ToLocalChecked();
+    Local<Object> module_obj = Nan::To<Object>(module_v).ToLocalChecked();
+    Local<String> cache_string = Nan::New<String>("_cache").ToLocalChecked();
+    Local<Value> cache_v = Nan::Get(module_obj, cache_string).ToLocalChecked();
+    Local<Object> cache_obj = Nan::To<Object>(cache_v).ToLocalChecked();
+    return scope.Escape(cache_obj);
 }
 
 // Check whether the filepath given looks like it's a file in the