perf(forms): use internal ngDevMode flag to tree-shake error messages in prod builds (#37821)

This commit adds a guard before throwing any forms errors. This will tree-shake
error messages which cannot be minified. It should also help to reduce the
bundle size of the `forms` package in production by ~20%.

Closes #37697

PR Close #37821

packages/core/test/bundling/forms/bundle.golden_symbols.json

@@ -221,15 +221,6 @@
   {
     "name": "FormControlName"
   },
-  {
-    "name": "FormErrorExamples_formControlName"
-  },
-  {
-    "name": "FormErrorExamples_formGroupName"
-  },
-  {
-    "name": "FormErrorExamples_ngModelGroup"
-  },
   {
     "name": "FormGroup"
   },
@@ -497,9 +488,6 @@
   {
     "name": "RangeValueAccessor"
   },
-  {
-    "name": "ReactiveErrors"
-  },
   {
     "name": "ReactiveFormsComponent"
   },
@@ -608,9 +596,6 @@
   {
     "name": "TRANSITION_ID"
   },
-  {
-    "name": "TemplateDrivenErrors"
-  },
   {
     "name": "TemplateFormsComponent"
   },
@@ -701,9 +686,6 @@
   {
     "name": "_keyMap"
   },
-  {
-    "name": "_noControlError"
-  },
   {
     "name": "_randomChar"
   },
@@ -716,9 +698,6 @@
   {
     "name": "_testabilityGetter"
   },
-  {
-    "name": "_throwError"
-  },
   {
     "name": "addComponentLogic"
   },
@@ -1628,9 +1607,6 @@
   {
     "name": "u"
   },
-  {
-    "name": "unimplemented"
-  },
   {
     "name": "unwrapRNode"
   },