fix(es/compat): Fix optional chaining (#7530)

**Description:**

This fixes a few bugs with optional chaining:

-
[`a?.c()`](https://play.swc.rs/?version=1.3.64&code=H4sIAAAAAAAAA9PXVwjOyC%2FNSVFISrXi0tdXSFSwtVXIK83JUbBXKM1LSU3LzEtNUbBSSNRL1tC05kq0h9AAouc%2F7DgAAAA%3D&config=H4sIAAAAAAAAA2VSu27DMAzc8xUC5wAZii7ZWnRJgXTKDxAKkyrQwyDpNEbgf69kxI4jexAk3olH3fm%2BMgYoXsFszT3vywchHQm2pa7cwXos28T0LRl4m0qnxJY%2BvD8wRsmHUGDllibGsYsYnN2FJrHWoCKfScudUbsv2LDARewEgI4CM24uezqj7b4oj4aauOpf5EdoT4pHVFxSmNDqS1tjNhvDbVQXKNuAraaA6iysC5DYWI8izs4uwIMOC%2F6cpL%2Bc%2FnanHwwkDVpaDJM5rdBn67y6WHv5eNCVfGpCzibDJ%2FQyw%2Fv1qtqAT0lqHWiQhfjVSumi4m2I3QYUy65RmNl0kdtS8OlvPWxfhTw0lnd45pv%2FstbTLOKuGeyzKYQULwIT08l%2B5BaJVf8PfP2zz7YCAAA%3D)
-
[`a?.b.c()`](https://play.swc.rs/?version=1.3.64&code=H4sIAAAAAAAAA9PXVwjOyC%2FNSVFISrXi0tdXSFSwtVXIK83JUbBXKM1LSU3LzEtNUbBSSNRL0kvW0LTmSrSHsQBsP8xLPAAAAA%3D%3D&config=H4sIAAAAAAAAA2VSu27DMAzc8xUC5wAZii7ZWnRJgXTKDxAKkyrQwyDpNEbgf69kxI4jexAk3olH3fm%2BMgYoXsFszT3vywchHQm2pa7cwXos28T0LRl4m0qnxJY%2BvD8wRsmHUGDllibGsYsYnN2FJrHWoCKfScudUbsv2LDARewEgI4CM24uezqj7b4oj4aauOpf5EdoT4pHVFxSmNDqS1tjNhvDbVQXKNuAraaA6iysC5DYWI8izs4uwIMOC%2F6cpL%2Bc%2FnanHwwkDVpaDJM5rdBn67y6WHv5eNCVfGpCzibDJ%2FQyw%2Fv1qtqAT0lqHWiQhfjVSumi4m2I3QYUy65RmNl0kdtS8OlvPWxfhTw0lnd45pv%2FstbTLOKuGeyzKYQULwIT08l%2B5BaJVf8PfP2zz7YCAAA%3D)
-
[`a.c?.()`](https://play.swc.rs/?version=1.3.64&code=H4sIAAAAAAAAAxWKsQ3AIAwEe6b4Ehq7J0IMkQGQYxMlkkUq9g80d1ccM87nm264eg7MiE2aomwvSiJNKAVjuqNiDuv3O7ohY4%2Bk4r7WdAQhrRRX%2FIwaKV1TAAAA&config=H4sIAAAAAAAAA2VSu27DMAzc8xUC5wAZii7ZWnRJgXTKDxAKkyrQwyDpNEbgf69kxI4jexAk3olH3fm%2BMgYoXsFszT3vywchHQm2pa7cwXos28T0LRl4m0qnxJY%2BvD8wRsmHUGDllibGsYsYnN2FJrHWoCKfScudUbsv2LDARewEgI4CM24uezqj7b4oj4aauOpf5EdoT4pHVFxSmNDqS1tjNhvDbVQXKNuAraaA6iysC5DYWI8izs4uwIMOC%2F6cpL%2Bc%2FnanHwwkDVpaDJM5rdBn67y6WHv5eNCVfGpCzibDJ%2FQyw%2Fv1qtqAT0lqHWiQhfjVSumi4m2I3QYUy65RmNl0kdtS8OlvPWxfhTw0lnd45pv%2FstbTLOKuGeyzKYQULwIT08l%2B5BaJVf8PfP2zz7YCAAA%3D)
-
[`a.b.c?.()`](https://play.swc.rs/?version=1.3.64&code=H4sIAAAAAAAAAyWLsQ3AIAwEe6b4Ehq7J0IMkQEQ2ESJZJGK%2FYNCdVfcMeO832mK1qNjhi%2B1tCJI2xYrtUASkBLGNEPGHNqvZ3RFxM5Jqtk%2FhMOtgSSTX%2FoBjF6UKV8AAAA%3D&config=H4sIAAAAAAAAA2VSu27DMAzc8xUC5wAZii7ZWnRJgXTKDxAKkyrQwyDpNEbgf69kxI4jexAk3olH3fm%2BMgYoXsFszT3vywchHQm2pa7cwXos28T0LRl4m0qnxJY%2BvD8wRsmHUGDllibGsYsYnN2FJrHWoCKfScudUbsv2LDARewEgI4CM24uezqj7b4oj4aauOpf5EdoT4pHVFxSmNDqS1tjNhvDbVQXKNuAraaA6iysC5DYWI8izs4uwIMOC%2F6cpL%2Bc%2FnanHwwkDVpaDJM5rdBn67y6WHv5eNCVfGpCzibDJ%2FQyw%2Fv1qtqAT0lqHWiQhfjVSumi4m2I3QYUy65RmNl0kdtS8OlvPWxfhTw0lnd45pv%2FstbTLOKuGeyzKYQULwIT08l%2B5BaJVf8PfP2zz7YCAAA%3D)
-
[`a?.b[c?.d]`](https://play.swc.rs/?version=1.3.64&code=H4sIAAAAAAAAA9PXVwjOyC%2FNSVFISrXi0tdX0IhPVLBVSNRUsLVVyCvNyVGwVyjLz0xRMFCwUohP1EuK1ohPBipIxq4gWS8l1por0R6oLtkezAYAJs%2FWxmEAAAA%3D&config=H4sIAAAAAAAAA2VSu27DMAzc8xUC5wAZii7ZWnRJgXTKDxAKkyrQwyDpNEbgf69kxI4jexAk3olH3fm%2BMgYoXsFszT3vywchHQm2pa7cwXos28T0LRl4m0qnxJY%2BvD8wRsmHUGDllibGsYsYnN2FJrHWoCKfScudUbsv2LDARewEgI4CM24uezqj7b4oj4aauOpf5EdoT4pHVFxSmNDqS1tjNhvDbVQXKNuAraaA6iysC5DYWI8izs4uwIMOC%2F6cpL%2Bc%2FnanHwwkDVpaDJM5rdBn67y6WHv5eNCVfGpCzibDJ%2FQyw%2Fv1qtqAT0lqHWiQhfjVSumi4m2I3QYUy65RmNl0kdtS8OlvPWxfhTw0lnd45pv%2FstbTLOKuGeyzKYQULwIT08l%2B5BaJVf8PfP2zz7YCAAA%3D)
- [`delete
foo?.bar`](https://play.swc.rs/?version=1.3.64&code=H4sIAAAAAAAAA9PXVwjOyC%2FNSVFISrXi0tdXSMvPV7C1VcgrzclRsFcoKSpNVbBSSEnNSS1JBcnpJSUWcSG49iA%2BAGcLTstEAAAA&config=H4sIAAAAAAAAA1WPSw7CMAxE9zlF5DULYIEEd%2BAQVnCrVPkpTiWqqncnTZMAO3vG42evQkqYWMFDrrnMTcDIFHufFV5cwndWgJRFVlGHBKfmTrxbAxqmIm2HAwnjSKmk%2BHq%2B3GsCjPdMWU5xpipZ7fSw%2FCKVtyESc9vcaRbdaOgfKCoUrH%2FNxayvpCXQccANvkMN1heD5mdL7leJ7QOQNa2NFgEAAA%3D%3D)
- [`function foo(a, b = a?.b)
{}`](https://play.swc.rs/?version=1.3.64&code=H4sIAAAAAAAAA9PXVwjOyC%2FNSVFISrXi0tdXSCvNSy7JzM9TSMvP10jUUUhSsFXQ0NBUsLVTqFYoSyxSiE%2B0VnjUsEyhVlNDU1OhupYLm45Ee70kkCQAp8DQOl8AAAA%3D&config=H4sIAAAAAAAAA22Rz07DMAzG73uKyOdJAw5I7Ii4cBjvYKXuyJQ%2Fle3AqmnvTltIm63cHH%2B%2F%2BPtkXzbGwEks7M1lKIeHMkZpE4e5NbU9HdH2b2QToyYeROVM2wVoinQgxQYV1wgTWr0Za8xuZzhHdYH2BjBrCqjOwnYUEhvrUcTZ6gP84bDia0g%2FOX2%2Ftx8YSDq0tAozMFnoNTuvLsp%2FckNf5FMXKI6ZW%2FRS6ddSzgX4lOTeBzpkIb5dpfRR8TzmJxtQLLtOoVrTSc5rw2W%2F92GXBIp8JJ0Gy9PD48s0dJIhpCZ7qq7cd%2FQLPsMMOTkUrBhAcNG1fcmzuf4AkV7gUzECAAA%3D)

It also optimizes the AST for runtime evaluation. Before, we constructed
a leftwards conditional tree (`(_a_b = (_a = a) == null ? void 0 : _a.b)
== null ? void 0 : _a_b.c`) instead of a rightward tree (`(_a = a) ==
null ? void 0 : (_a_b = _a.b) == null ? void 0 : _a_b.c`), which
required multiple `== null` checks after the first nullish is found.

**Related issue:**

 - Closes #7531.

Author: jridgewell

crates/swc/tests/fixture/issues-1xxx/1333/case3/output/index.js

@@ -75,8 +75,8 @@ class RequestHandler {
      * @param {Response} res
      * @return {* | Promise<any>}
      */ static async parseResponse(res) {
-        var _res_headers_get_startsWith, _this;
-        if ((_this = res.headers.get("Content-Type")) === null || _this === void 0 ? void 0 : (_res_headers_get_startsWith = _this.startsWith) === null || _res_headers_get_startsWith === void 0 ? void 0 : _res_headers_get_startsWith.call(_this, "application/json")) {
+        var _res_headers_get;
+        if ((_res_headers_get = res.headers.get("Content-Type")) === null || _res_headers_get === void 0 ? void 0 : _res_headers_get.startsWith("application/json")) {
             return await res.json();
         }
         return res.buffer();

crates/swc/tests/fixture/issues-2xxx/2020/case1/output/index.js

@@ -1 +1 @@
-"use strict";const createRegisterItems=registerType=>async(a,b)=>{var _root;const a=(_root=root)===null||_root===void 0?void 0:_root.test};
+"use strict";const createRegisterItems=registerType=>async(a,b)=>{const a=root?.test};