No error in toplevel script files

Only issue "no top-level return" error for modules, not scripts,
regardless of whether it's TS or JS.

Author: sandersn

src/compiler/checker.ts

@@ -38913,7 +38913,9 @@ namespace ts {
             }
 
             if (!container) {
-                grammarErrorOnFirstToken(node, Diagnostics.A_return_statement_can_only_be_used_within_a_function_body);
+                if (!!getSourceFileOfNode(node).externalModuleIndicator) {
+                    grammarErrorOnFirstToken(node, Diagnostics.A_return_statement_can_only_be_used_within_a_function_body);
+                }
                 return;
             }
 

src/compiler/program.ts

@@ -913,6 +913,7 @@ namespace ts {
         Diagnostics.A_rest_parameter_cannot_have_an_initializer.code,
         Diagnostics.A_rest_parameter_must_be_last_in_a_parameter_list.code,
         Diagnostics.A_rest_parameter_or_binding_pattern_may_not_have_a_trailing_comma.code,
+        Diagnostics.A_return_statement_can_only_be_used_within_a_function_body.code,
         Diagnostics.A_return_statement_cannot_be_used_inside_a_class_static_block.code,
         Diagnostics.A_set_accessor_cannot_have_rest_parameter.code,
         Diagnostics.A_set_accessor_must_have_exactly_one_parameter.code,

tests/baselines/reference/ambientWithStatements.errors.txt

@@ -1,10 +1,9 @@
 tests/cases/compiler/ambientWithStatements.ts(2,5): error TS1036: Statements are not allowed in ambient contexts.
 tests/cases/compiler/ambientWithStatements.ts(3,5): error TS1104: A 'continue' statement can only be used within an enclosing iteration statement.
-tests/cases/compiler/ambientWithStatements.ts(11,5): error TS1108: A 'return' statement can only be used within a function body.
 tests/cases/compiler/ambientWithStatements.ts(25,5): error TS2410: The 'with' statement is not supported. All symbols in a 'with' block will have type 'any'.
 
 
-==== tests/cases/compiler/ambientWithStatements.ts (4 errors) ====
+==== tests/cases/compiler/ambientWithStatements.ts (3 errors) ====
     declare module M {
         break;
         ~~~~~
@@ -20,8 +19,6 @@ tests/cases/compiler/ambientWithStatements.ts(25,5): error TS2410: The 'with' st
         1;
         L: var y;
         return;
-        ~~~~~~
-!!! error TS1108: A 'return' statement can only be used within a function body.
         switch (x) {
             case 1:
                 break;

tests/baselines/reference/asiReturn.errors.txt

@@ -6,12 +6,12 @@ return this.edit(role)
 >this.edit : any
 >this : typeof globalThis
 >edit : any
->role : any
+>role : error
 
     .then((role: Role) =>
 >then : any
 >(role: Role) =>        this.roleService.add(role)            .then((data: ng.IHttpPromiseCallbackArg<Role>) => data.data) : (role: Role) => any
->role : Role
+>role : error
 
         this.roleService.add(role)
 >this.roleService.add(role)            .then((data: ng.IHttpPromiseCallbackArg<Role>) => data.data) : any
@@ -22,14 +22,14 @@ return this.edit(role)
 >this : typeof globalThis
 >roleService : any
 >add : any
->role : Role
+>role : error
 
             .then((data: ng.IHttpPromiseCallbackArg<Role>) => data.data));
 >then : any
 >(data: ng.IHttpPromiseCallbackArg<Role>) => data.data : (data: ng.IHttpPromiseCallbackArg<Role>) => any
->data : ng.IHttpPromiseCallbackArg<Role>
+>data : error
 >ng : any
->data.data : any
+>data.data : error
 >data : ng.IHttpPromiseCallbackArg<Role>
 >data : any
 

tests/baselines/reference/fileWithNextLine3.errors.txt

@@ -1,11 +1,8 @@
 tests/cases/conformance/parser/ecmascript5/ErrorRecovery/VariableLists/parserErrorRecovery_VariableList1.ts(1,6): error TS1009: Trailing comma not allowed.
-tests/cases/conformance/parser/ecmascript5/ErrorRecovery/VariableLists/parserErrorRecovery_VariableList1.ts(2,1): error TS1108: A 'return' statement can only be used within a function body.
 
 
-==== tests/cases/conformance/parser/ecmascript5/ErrorRecovery/VariableLists/parserErrorRecovery_VariableList1.ts (2 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/ErrorRecovery/VariableLists/parserErrorRecovery_VariableList1.ts (1 errors) ====
     var a,
          ~
 !!! error TS1009: Trailing comma not allowed.
-    return;
-    ~~~~~~
-!!! error TS1108: A 'return' statement can only be used within a function body.
+    return;

tests/baselines/reference/multiLinePropertyAccessAndArrowFunctionIndent1.errors.txt

@@ -1,13 +1,10 @@
 tests/cases/conformance/parser/ecmascript5/parserNotRegex1.ts(1,7): error TS2304: Cannot find name 'a'.
-tests/cases/conformance/parser/ecmascript5/parserNotRegex1.ts(3,5): error TS1108: A 'return' statement can only be used within a function body.
 
 
-==== tests/cases/conformance/parser/ecmascript5/parserNotRegex1.ts (2 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/parserNotRegex1.ts (1 errors) ====
       if (a.indexOf(-(4/3)))      // We should not get a regex here because of the / in the comment.
           ~
 !!! error TS2304: Cannot find name 'a'.
       {
         return true;
-        ~~~~~~
-!!! error TS1108: A 'return' statement can only be used within a function body.
       }