fix(core): reenable decorator downleveling for Angular npm packages (angular#37317)

In angular#37221 we disabled tsickle passes from transforming the tsc output that is used to publish all
Angular framework and components packages (@angular/*).

This change however revealed a bug in the ngc that caused __decorate and __metadata calls to still
be emitted in the JS code even though we don't depend on them.

Additionally it was these calls that caused code in @angular/material packages to fail at runtime
due to circular dependency in the emitted decorator code documeted as
microsoft/TypeScript#27519.

This change partially rolls back angular#37221 by reenabling the decorator to static fields (static
properties) downleveling.

This is just a temporary workaround while we are also fixing root cause in `ngc` - tracked as
FW-2199.

Resolves FW-2198.
Related to FW-2196

PR Close angular#37317

Author: IgorMinar

goldens/size-tracking/integration-payloads.json

@@ -61,8 +61,8 @@
         "bundle": "TODO(i): temporarily increase the payload size limit from 105779 - this is due to a closure issue related to ESM reexports that still needs to be investigated",
         "bundle": "TODO(i): we should define ngDevMode to false in Closure, but --define only works in the global scope.",
         "bundle": "TODO(i): (FW-2164) TS 3.9 new class shape seems to have broken Closure in big ways. The size went from 169991 to 252338",
-        "bundle": "TODO(i): after removal of tsickle from ngc-wrapped / ng_package, we had to switch to SIMPLE optimizations which increased the size from 252338 to 1218969, see PR#37221 for more info",
-        "bundle": 1218969
+        "bundle": "TODO(i): after removal of tsickle from ngc-wrapped / ng_package, we had to switch to SIMPLE optimizations which increased the size from 252338 to 1200475, see PR#37221 and PR#37317 for more info",
+        "bundle": 1200475
       }
     }
   }

integration/ngcc/test.sh

@@ -90,13 +90,9 @@ assertSucceeded "Expected 'ngcc' to log 'Compiling'."
   grep "ApplicationModule.ɵmod = ɵngcc0.ɵɵdefineNgModule" node_modules/@angular/core/esm2015/src/application_module.js
   assertSucceeded "Expected 'ngcc' to correctly compile 'ApplicationModule' in '@angular/core' (esm2015)."
 
-# TODO: This assertion is disabled because @angular/core is no longer processed by tsickle which creates the static properties.
-#       We should either remove this assertion or use a syntentic JS file as input.
-#       Discuss with the ngcc folks.
-#
 # Did it place the `setClassMetadata` call correctly?
-#  cat node_modules/@angular/core/fesm2015/core.js | awk 'ORS=" "' | grep "ApplicationRef.ctorParameters.*setClassMetadata(ApplicationRef"
-#  assertSucceeded "Expected 'ngcc' to place 'setClassMetadata' after static properties like 'ctorParameters' in '@angular/core' (fesm2015)."
+  cat node_modules/@angular/core/fesm2015/core.js | awk 'ORS=" "' | grep "ApplicationRef.ctorParameters.*setClassMetadata(ApplicationRef"
+  assertSucceeded "Expected 'ngcc' to place 'setClassMetadata' after static properties like 'ctorParameters' in '@angular/core' (fesm2015)."
 
 
 # Did it transform @angular/core typing files correctly?
@@ -123,13 +119,19 @@ assertSucceeded "Expected 'ngcc' to log 'Compiling'."
   assertSucceeded "Expected 'ngcc' to generate an abstract directive definition for 'MatMenuBase' in '@angular/material' (esm5)."
 
 
+# TODO: This assertion is disabled because @angular/common no longer contains __decorate calls.
+#       We should either remove this assertion or use a syntentic JS file as input.
+#       Discuss with the ngcc folks.
 # Did it handle namespace imported decorators in UMD using `__decorate` syntax?
-  grep "type: i0.Injectable" node_modules/@angular/common/bundles/common.umd.js
-  assertSucceeded "Expected 'ngcc' to correctly handle '__decorate' syntax in '@angular/common' (umd)."
+  #grep "type: i0.Injectable" node_modules/@angular/common/bundles/common.umd.js
+  #assertSucceeded "Expected 'ngcc' to correctly handle '__decorate' syntax in '@angular/common' (umd)."
 
+# TODO: This assertion is disabled because @angular/common no longer contains __decorate calls.
+#       We should either remove this assertion or use a syntentic JS file as input.
+#       Discuss with the ngcc folks.
   # (and ensure the @angular/common package is indeed using `__decorate` syntax)
-  grep "JsonPipe = __decorate(" node_modules/@angular/common/bundles/common.umd.js.__ivy_ngcc_bak
-  assertSucceeded "Expected '@angular/common' (umd) to actually use '__decorate' syntax."
+  #grep "JsonPipe = __decorate(" node_modules/@angular/common/bundles/common.umd.js.__ivy_ngcc_bak
+  #assertSucceeded "Expected '@angular/common' (umd) to actually use '__decorate' syntax."
 
 
 # Did it handle namespace imported decorators in UMD using static properties?

integration/side-effects/snapshots/animations-browser/esm2015.js

@@ -1,5 +1,3 @@
-import "tslib";
-
 import "@angular/animations";
 
 import "@angular/core";

integration/side-effects/snapshots/common/esm2015.js

@@ -1,3 +1 @@
-import "tslib";
-
 import "@angular/core";

integration/side-effects/snapshots/core/esm2015.js

@@ -1,7 +1,5 @@
 import "rxjs";
 
-import "tslib";
-
 import "rxjs/operators";
 
 const __globalThis = "undefined" !== typeof globalThis && globalThis;

integration/side-effects/snapshots/forms/esm2015.js

@@ -1,5 +1,3 @@
-import "tslib";
-
 import "@angular/core";
 
 import "@angular/common";

integration/side-effects/snapshots/platform-browser/esm2015.js

@@ -1,5 +1,3 @@
-import "tslib";
-
 import "@angular/common";
 
 import "@angular/core";

integration/side-effects/snapshots/router/esm2015.js

@@ -1,5 +1,3 @@
-import "tslib";
-
 import "@angular/common";
 
 import "@angular/core";

packages/bazel/src/ngc-wrapped/index.ts

@@ -191,13 +191,12 @@ export function compile({
     fileLoader = new UncachedFileLoader();
   }
 
+  compilerOpts.annotationsAs = 'static fields';
   if (!bazelOpts.es5Mode) {
     if (bazelOpts.workspaceName === 'google3') {
       compilerOpts.annotateForClosureCompiler = true;
-      compilerOpts.annotationsAs = 'static fields';
     } else {
       compilerOpts.annotateForClosureCompiler = false;
-      compilerOpts.annotationsAs = 'decorators';
     }
   }
 
@@ -278,11 +277,13 @@ export function compile({
     };
   }
 
-  // Prevent tsickle adding any types at all if we don't want closure compiler annotations.
   if (compilerOpts.annotateForClosureCompiler) {
     bazelHost.transformTypesToClosure = true;
+  }
+  if (compilerOpts.annotateForClosureCompiler || compilerOpts.annotationsAs === 'static fields') {
     bazelHost.transformDecorators = true;
   }
+
   const origBazelHostFileExist = bazelHost.fileExists;
   bazelHost.fileExists = (fileName: string) => {
     if (NGC_ASSETS.test(fileName)) {