WebGPURenderer: Consistent `enable()` and `disable()` usage. (#32503)

src/renderers/webgl-fallback/WebGLBackend.js

@@ -815,7 +815,7 @@ class WebGLBackend extends Backend {
 		if ( this.discard === false ) {
 
 			// required here to handle async behaviour of render.compute()
-			gl.enable( gl.RASTERIZER_DISCARD );
+			state.enable( gl.RASTERIZER_DISCARD );
 			this.discard = true;
 
 		}
@@ -901,11 +901,11 @@ class WebGLBackend extends Backend {
 	 */
 	finishCompute( computeGroup ) {
 
-		const gl = this.gl;
+		const { state, gl } = this;
 
 		this.discard = false;
 
-		gl.disable( gl.RASTERIZER_DISCARD );
+		state.disable( gl.RASTERIZER_DISCARD );
 
 		this.prepareTimestampBuffer( TimestampQuery.COMPUTE, this.getTimestampUID( computeGroup ) );
 

src/renderers/webgl-fallback/utils/WebGLState.js

@@ -625,11 +625,11 @@ class WebGLState {
 
 		if ( boolean ) {
 
-			gl.enable( gl.SCISSOR_TEST );
+			this.enable( gl.SCISSOR_TEST );
 
 		} else {
 
-			gl.disable( gl.SCISSOR_TEST );
+			this.disable( gl.SCISSOR_TEST );
 
 		}