gin: Correct ToV8Traits<T, true>::TryConvertToV8.

A context was erroneously passed where an isolate is now expected.

Introduced in:
  https://chromium.googlesource.com/chromium/src/+/eb8a2f1758cf71197e44bdbd79e59105ad845b51

Change-Id: I1b69c4533c7f607e6813c532eae78a2a0c7d50ca
Reviewed-on: https://chromium-review.googlesource.com/964390
Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Commit-Queue: Jeremy Roman <jbroman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543740}

gin/converter.h

@@ -231,11 +231,7 @@ struct ToV8Traits<T, true> {
   static bool TryConvertToV8(v8::Isolate* isolate,
                              T input,
                              v8::Local<v8::Value>* output) {
-    auto maybe = ConvertToV8(isolate->GetCurrentContext(), input);
-    if (maybe.IsEmpty())
-      return false;
-    *output = maybe.ToLocalChecked();
-    return true;
+    return ConvertToV8(isolate, input).ToLocal(output);
   }
 };
 

gin/converter_unittest.cc

@@ -167,10 +167,15 @@ TEST_F(ConverterTest, VectorOfWrappables) {
   v8::MaybeLocal<v8::Value> maybe = ConvertToV8(isolate, vector);
   v8::Local<v8::Value> array;
   ASSERT_TRUE(maybe.ToLocal(&array));
+  v8::Local<v8::Value> array2;
+  ASSERT_TRUE(TryConvertToV8(isolate, vector, &array2));
 
   std::vector<MyObject*> out_value;
   ASSERT_TRUE(ConvertFromV8(isolate, array, &out_value));
   EXPECT_THAT(out_value, testing::ContainerEq(vector));
+  std::vector<MyObject*> out_value2;
+  ASSERT_TRUE(ConvertFromV8(isolate, array2, &out_value2));
+  EXPECT_THAT(out_value2, testing::ContainerEq(vector));
 }
 
 }  // namespace gin