Improve components for PhantomJs compatibility

...cripts/merge_conflicts/components/diff_file_editor.js.es6

...s/merge_conflicts/components/inline_conflict_lines.js.es6

.../merge_conflicts/components/parallel_conflict_line.js.es6

...merge_conflicts/components/parallel_conflict_lines.js.es6

...s/javascripts/merge_conflicts/merge_conflict_store.js.es6

...javascripts/merge_conflicts/merge_conflicts_bundle.js.es6

...ripts/merge_conflicts/mixins/line_conflict_actions.js.es6

...scripts/merge_conflicts/mixins/line_conflict_utils.js.es6

app/views/projects/merge_requests/conflicts.html.haml

...projects/merge_requests/conflicts/_commit_stats.html.haml

...ects/merge_requests/conflicts/_diff_file_editor.html.haml

...ests/conflicts/_resolve_mode_interactive_inline.html.haml

...ts/conflicts/_resolve_mode_interactive_parallel.html.haml

...requests/conflicts/components/_diff_file_editor.html.haml

...sts/conflicts/components/_inline_conflict_lines.html.haml

...ts/conflicts/components/_parallel_conflict_line.html.haml

...s/conflicts/components/_parallel_conflict_lines.html.haml