Report UI: exc. time is wrongly zeroed for truncated function calls

[NoiseByNorthwest]

When a function call's span overlaps with the current time range, its exclusive time is zeroed which can cause accuracy issues in the flatprofile view. Here is an example where the handleRaw() & dispatch() functions have a 0 exclusive time in the flat profile view which is wrong and inconsistent with what we can see in the timeline. Furthermore, the sum of the exclusive time percentages must always be 100.