Bug 1955085 - build(webgpu): update WGPU to c6286791febc64cf8ef054b5356c2669327ef51c r=webgpu-reviewers,supply-chain-reviewers,nical

WRT WebGPU CTS, we have some interesting changes:

- Promotions from tier 3 to tier 2:
	- `webgpu:shader,execution,expression,call,builtin,textureStore:out_of_bounds:*`
	- All of `webgpu:shader,execution,expression,binary,ai_arithmetic:*` on Windows and Linux.
	- Some of `webgpu:shader,execution,expression,binary,bitwise:*` on Windows and Linux:
		- `…:bitwise_and:*`
		- `…:bitwise_exclusive_or:*`
		- `…:bitwise_or:*`
	- `webgpu:shader,execution,expression,call,builtin,textureStore:out_of_bounds:*`
	- Some of `webgpu:shader,execution,expression,unary,*` on Windows and Linux:
		- `…,ai_assignment:abstract:*`
		- `…,ai_assignment:abstract:*`
		- `…,ai_complement:complement:*`
	- `webgpu:shader,execution,limits:switch_case_selectors:*` on Windows and macOS.
	- `webgpu:shader,execution,limits:workgroup_array_byte_size_override:*` on all but Windows debug.
	- `webgpu:shader,execution,zero_init:compute,zero_init:*` on macOS.
	- `webgpu:shader,validation,expression,access,vector:abstract:*`
	- `webgpu:shader,validation,expression,call,builtin,textureGather:offset_argument,non_const:*` on all but Windows debug.
	- `webgpu:shader,validation,expression,call,builtin,textureSample:offset_argument,non_const:*`
	- `webgpu:shader,validation,expression,call,builtin,textureSampleGrad:offset_argument,non_const:*`
	- Most of `webgpu:shader,validation,statement,switch:*`:
		- `…:case_types_match:*`
		- `…:condition_type_match_case_type:*`
		- `…:parse:*`

- Demotions from tier 2 to tier 3:
	- `webgpu:api,validation,capability_checks,limits,maxColorAttachmentBytesPerSample:beginRenderPass,at_over:*`

- Otherwise notable potential regressions:
	- `webgpu:shader,validation,expression,matrix,mul:overflow_scalar_abstract:*`

Differential Revision: https://phabricator.services.mozilla.com/D242218

.cargo/config.toml.in

@@ -40,9 +40,9 @@ git = "https://github.com/franziskuskiefer/cose-rust"
 rev = "43c22248d136c8b38fe42ea709d08da6355cf04b"
 replace-with = "vendored-sources"
 
-[source."git+https://github.com/gfx-rs/wgpu?rev=dc02f91ffe1feab8c35d3fdf41f61a62a5004d2c"]
+[source."git+https://github.com/gfx-rs/wgpu?rev=c6286791febc64cf8ef054b5356c2669327ef51c"]
 git = "https://github.com/gfx-rs/wgpu"
-rev = "dc02f91ffe1feab8c35d3fdf41f61a62a5004d2c"
+rev = "c6286791febc64cf8ef054b5356c2669327ef51c"
 replace-with = "vendored-sources"
 
 [source."git+https://github.com/glandium/rust-objc?rev=4de89f5aa9851ceca4d40e7ac1e2759410c04324"]