gh-140677 Improve heatmap colors by ivonastojanovic · Pull Request #142241 · python/cpython

Previously, colors were generated in HeatmapCollector based on
intensity, and the same colors were used for both light and dark
themes. As a result, the displayed colors didn’t always match the
color legend for the selected theme.

To fix this, we now compute only the intensity for both self and
total samples in HeatmapCollector. The actual color is chosen later
based on that intensity and the active theme, ensuring the lines
correctly follow the theme-specific color legend.

The _color_cache itself is no longer needed because colors are no
longer generated in HeatmapCollector.