Before this change, we were using the labels from the original chartData to the chart builder, and we would then apply our collapse function on each dataset which could change the labels and cause a mismatch.
This was very visible when using quarterly periods on consolidated pageviews.
Note that this commit will also disable daily grouping for datasets with more than 30 data points. This will also smartly do the grouping by month when grouping a full year.
We want to wrap the `Ember.run.debounce` function and internally call `Ember.run` instead when running tests.
This commit changes discourseDebounce to work the same way as `Ember.run.debounce`.
Now that `discourseDebounce` works exactly like `Ember.run.debounce`, let's replace it and only use `DiscourseDebounce` from now on.
Move debounce to discourse-common to be able to reuse it in different bundles
Keep old debounce file for backwards-compatibility