1521995 - Provide nursery usage information to the gecko profiler's counters

Status: NEW

(Core :: JavaScript: GC, enhancement, P3)

Description

[Paul Bone [:pbone]]

Bug 1518061 will add counters for the memory usage of the tenured heap. but that wont count the nursery. This bug is for doing the same for the nursery. The nursery size must be calculated carefully since we don't want to add any extra code to the hot paths. Therefore it will be best to compute the nursery used size by subetracting the beginning of the current chunk from the current position in that chunk, plus the usable chunk size of the earlier chunks.