72a3317656
This adds a new timeline renderer using a plain canvas element, replacing the d3 and svg-based renderer. This new implementation greatly improves timeline performance, especially on less powerful graphics cards, and more than doubles the resulting framerate while panning the view by aggressively caching previously rendered chart regions. Additionally, worst-case memory usage is greatly reduced during heavier periods of user interaction. This new implementation also removes several previous limitations. Due to cached rendering a nearly unlimited number of objects can be shown at any time with no performance impact, so small objects never need to be hidden from view at any zoom level. Also, view transitions can now be smoothly animated, and reach a stable framerate even on older mobile devices. Change-Id: Ib883e056270eff688b4b4a0c340eaea20cceb181