Merge most of the horizontalBar controller into the bar one but also fix stack groups and bar positioning when scales are stacked or when a min and/or max tick values are explicitly defined. Note that this is a breaking change for derived controllers that rely on the following removed methods: `calculateBarBase`, `calculateBarX`, `calculateBarY`, `calculateBarWidth` and `calculateBarHeight`.
* Undo fix for #3585 since it has broken the stacked bar charts when the axis has a user defined minimum value.
* When a value of 0 is requested for a vertical logarithmic axis, return the bottom point
In order to take full advantage of the new plugin hooks called before and after a dataset is drawn, all drawing operations must happen on stable meta data, so make sure that transitions are performed before.
Fix bar draw issue.
1. `Chart.elements.Rectangle.draw` function supports both horizontal and vertical bar.
2. Corrected bar position at minus.
3. Adjust bar size when `borderWidth` is set.
4. Adjust bar size when `borderSkipped` is set.
5. Adjust `borderWidth` with value near 0(base).
6. Update test.
This change allows for smaller minified code in the final version, resulting in a smaller file size. Some files had previously used _this, but that has been changed to me to keep consistency throughout the project.
Data controllers should now rarely implement addElements and addElementAndReset but instead should define dataElementType (and optionally datasetElementType). Also remove some dead code (e.g. numBars, colorForNewElement, etc.).
Updated all chart types to use the helper.getHoverColor. Pattern fills can now be specified for both fill and line portions of a chart. Updates chartjs/Chart.js#1323
* Horizontal bar chart type
* Mentioned horizontal bar chart in bar documentation
* Sample file for horizontal bar chart
* Missing semicolon
* Fix for borderSkipped index
Introduced a new meta.hidden 3 states flag (null|true|false) to be able to override dataset.hidden when interacting with the chart (i.e., true or false to ignore the dataset.hidden value). This is required in order to be able to correctly share dataset.hidden between multiple charts.
For example: 2 charts are sharing the same data and dataset.hidden is initially false: the dataset will be displayed on both charts because meta.hidden is null. If the user clicks the legend of the first chart, meta.hidden is changed to true and the dataset is only hidden on the first chart. If dataset.hidden changes, only the second chart will have the dataset visibility updated and that until the user click again on the first chart legend, switching the meta.hidden to null.
Dataset effective type is now stored under meta.type, allowing many charts to share the same dataset but with different types. Also move dataset.bar flag to meta.bar.
Meta info are now scoped by chart and moved under the dataset._meta map { chart.id -> meta }. Meta for a specific chart (and dataset) can be accessed using chart.getDatasetMeta(datasetIndex) or from the dataset controller using getMeta(). Note that helpers.uid() now generates an int (instead of a string) to make lookups in the _meta map faster.
