fix 31012 allow noEmitOnError with isolatedModules (#34) (#31043)

fix #31012

Since the purpose of isolatedModules: true is to
do extra validation to ensure that separate
compilation is safe

Allowing emit in the presence of errors is
compatible with that intention.

Signed-off-by: Max Heiber <max.heiber@gmail.com>

src/compiler/program.ts

@@ -2707,10 +2707,6 @@ namespace ts {
                     createDiagnosticForOptionName(Diagnostics.Option_0_cannot_be_specified_with_option_1, getEmitDeclarationOptionName(options), "isolatedModules");
                 }
 
-                if (options.noEmitOnError) {
-                    createDiagnosticForOptionName(Diagnostics.Option_0_cannot_be_specified_with_option_1, "noEmitOnError", "isolatedModules");
-                }
-
                 if (options.out) {
                     createDiagnosticForOptionName(Diagnostics.Option_0_cannot_be_specified_with_option_1, "out", "isolatedModules");
                 }

tests/baselines/reference/isolatedModulesNoEmitOnError.errors.txt

@@ -1,6 +1,7 @@
-error TS5053: Option 'noEmitOnError' cannot be specified with option 'isolatedModules'.
+tests/cases/compiler/file1.ts(1,14): error TS2322: Type '3' is not assignable to type 'string'.
 
 
-!!! error TS5053: Option 'noEmitOnError' cannot be specified with option 'isolatedModules'.
-==== tests/cases/compiler/file1.ts (0 errors) ====
-    export var x;
+==== tests/cases/compiler/file1.ts (1 errors) ====
+    export const x: string = 3;
+                 ~
+!!! error TS2322: Type '3' is not assignable to type 'string'.

tests/baselines/reference/isolatedModulesNoEmitOnError.symbols

@@ -1,4 +1,4 @@
 === tests/cases/compiler/file1.ts ===
-export var x;
->x : Symbol(x, Decl(file1.ts, 0, 10))
+export const x: string = 3;
+>x : Symbol(x, Decl(file1.ts, 0, 12))
 

tests/baselines/reference/isolatedModulesNoEmitOnError.types

@@ -1,4 +1,5 @@
 === tests/cases/compiler/file1.ts ===
-export var x;
->x : any
+export const x: string = 3;
+>x : string
+>3 : 3
 

tests/cases/compiler/isolatedModulesNoEmitOnError.ts

@@ -3,4 +3,4 @@
 // @target: es6
 
 // @filename: file1.ts
-export var x;
+export const x: string = 3;