Auto merge of #26336 - szeged:mmatyas__webgl_fns_getparam4, r=jdm

Add support for WebGL2 MIN_PROGRAM_TEXEL_OFFSET

Improves the support of the WebGL2 `MIN_PROGRAM_TEXEL_OFFSET` property (ie. stores it as a signed integer) and adds support for querying it using GetParameter.

See: https://www.khronos.org/registry/webgl/specs/latest/2.0/#3.7.2

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cc @jdm @zakorgy

Depends on #26333 because they touch the same test files.

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components/canvas_traits/webgl.rs

@@ -1411,7 +1411,7 @@ pub struct GLLimits {
     pub max_draw_buffers: u32,
     pub max_color_attachments: u32,
     pub max_uniform_buffer_bindings: u32,
-    pub min_program_texel_offset: u32,
+    pub min_program_texel_offset: i32,
     pub max_program_texel_offset: u32,
     pub max_uniform_block_size: u64,
     pub max_combined_uniform_blocks: u32,