Applied code changes to fresh clone.

Ideally, this test would exercise the block in StreamingBaseHtmlProvider.getTemplate():
`
                final String mixin = Iterables.find(copy, acceptWhenTemplateMapContainsKey, null);
                if (mixin != null) {
                    LOGGER.debug("Matched mixin type: {}", mixin);
                    template = templatesMap.get(mixin);
                }
`

However, the test as written results in `mixin` being null and the `if` block above being skipped.