LibWeb/HTML: Add CanvasColorType

We don't implement the affected algorithms, and so the only change to
apply here is adding the dictionary member to IDL.

Corresponds to a5853ca8fa

Libraries/LibWeb/HTML/CanvasRenderingContext2D.idl

@@ -17,11 +17,13 @@
 #import <HTML/Canvas/CanvasUserInterface.idl>
 
 enum PredefinedColorSpace { "srgb", "display-p3" };
+enum CanvasColorType { "unorm8", "float16" };
 
 dictionary CanvasRenderingContext2DSettings {
     boolean alpha = true;
     boolean desynchronized = false;
     PredefinedColorSpace colorSpace = "srgb";
+    CanvasColorType colorType = "unorm8";
     boolean willReadFrequently = false;
 };