Radial gradient broken in CoreGraphics

[alexrodi]

Noticed on one of my projects that juce::ColourGradient with isRadial set to true no longer blends the rgb components correctly (on macOS at least, haven’t had time to test on other machines).

Wrote this little example to demonstrate the problem:

void MainComponent::paint (juce::Graphics& g)
{
    g.fillAll(juce::Colours::black);
    
    
    g.setGradientFill({
        juce::Colours::white, {0.0f, 0.0f},
        juce::Colours::red.withAlpha(0.0f), {0.0f, (float)getHeight()}
        , false
    });
    g.fillRect(getLocalBounds().removeFromLeft(getWidth() / 2));
    
    
    g.setGradientFill({
        juce::Colours::white, {(float)getWidth()*0.5f, 0.0f},
        juce::Colours::red.withAlpha(0.0f), {(float)getWidth()*0.5f, (float)getHeight()}
        , true
    });
    g.fillRect(getLocalBounds().removeFromRight(getWidth() / 2));
}

As you can see, the linear gradient is drawn correctly with the white blending into red before it becomes transparent.

Another curious observation: I can tell that in the very first frame the window displays, the radial gradient appears to be drawn correctly and immediatly gets redrawn as shown in the image.

JUCE v8.0.8

EDIT: can confirm the very first frame IS drawn correctly - on one of the runs, it happened that no redraws were done and the first frame stuck around and the gradients were seamless (as expected).