[Impeller] Linear to sRGB Gamma filter implementation.

[betrevisan]

The changes proposed in this PR implement the Linear Gamma to sRGB filter in Impeller alongside accompanying tests.

Below is a screenshot of the playground. The image on the left is the unfiltered image and the one on the right is the filtered one.

Solves flutter/flutter#109738.

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[bdero]

This needs to be rebased as RenderFilter has changed. It no longer takes a RenderPass and it now returns a Snapshot.

[bdero]

Just realized this is a separate PR to #35441. I don't think these need to be landed as totally distinct filters given the only difference between the two should be the fragment shader (and the fragment shader should require the exact same uniform/varying layout).

I recommend renaming this filter to ColorSpaceFilterContents, adding an enum option to specify the conversion operation (i.e. kLinearToSrgb and kSrgbToLinear), and do the command creation in a template with a Pipeline type parameter. See the AdvancedBlend function in blend_filter_contents.cc for an example of this.

[bdero]

LGTM, thanks! Since these work, we should definitely land them. These conversions can be combined later in follow-ups.