WebGPURenderer: Fix clear for default framebuffer

[RenaudRohlinger]

Related issue: #30329 (comment)

Description

Fixes clear when rendering to default framebuffer as we don't need to forward the clearColorValue to any renderContext since it's directly accessible via color, depth, stencil.

This contribution is funded by Utsubo

[github-actions]

📦 Bundle size

Full ESM build, minified and gzipped.

	Before	After	Diff
WebGL	336.12 78.22	336.12 78.22	+0 B +0 B
WebGPU	516.99 143.53	516.99 143.53	+0 B +2 B
WebGPU Nodes	516.45 143.43	516.45 143.43	+0 B +1 B

🌳 Bundle size after tree-shaking

Minimal build including a renderer, camera, empty scene, and dependencies.

	Before	After	Diff
WebGL	465.17 112.09	465.17 112.09	+0 B +0 B
WebGPU	588.99 159.73	588.99 159.73	+0 B +2 B
WebGPU Nodes	544.35 149.29	544.35 149.29	+0 B +1 B

[sunag]

Could we move this assignment to conditional above in renderTarget !== null? since renderContext is only assigned once

three.js/src/renderers/common/Renderer.js

Lines 1894 to 1918 in 65ef1be

	let renderContext = null;
	if ( renderTarget !== null ) {
	this._textures.updateRenderTarget( renderTarget );
	const renderTargetData = this._textures.get( renderTarget );
	renderContext = this._renderContexts.getForClear( renderTarget );
	renderContext.textures = renderTargetData.textures;
	renderContext.depthTexture = renderTargetData.depthTexture;
	renderContext.width = renderTargetData.width;
	renderContext.height = renderTargetData.height;
	renderContext.renderTarget = renderTarget;
	renderContext.depth = renderTarget.depthBuffer;
	renderContext.stencil = renderTarget.stencilBuffer;
	}
	// #30329
	if ( renderContext !== null ) {
	renderContext.clearColorValue = this._clearColor;
	}

[RenaudRohlinger]

Indeed