src/vs/workbench/api/common/extHostWorkspace.ts/ExtHostWorkspace/registerEditSessionIdentityProvider
class ExtHostWorkspace:	registerEditSessionIdentityProvider(scheme: string, provider: vscode.EditSessionIdentityProvider) {
		if (this._editSessionIdentityProviders.has(scheme)) {
			throw new Error(`A provider has already been registered for scheme ${scheme}`);
		}

		this._editSessionIdentityProviders.set(scheme, provider);
		const outgoingScheme = this._uriTransformerService.transformOutgoingScheme(scheme);
		const handle = this._providerHandlePool++;
		this._proxy.$registerEditSessionIdentityProvider(handle, outgoingScheme);

		return toDisposable(() => {
			this._editSessionIdentityProviders.delete(scheme);
			this._proxy.$unregisterEditSessionIdentityProvider(handle);
		});
	}