Fix panic in printer when type-only export is body of an if statement

internal/printer/emitcontext.go

@@ -943,11 +943,11 @@ func (c *EmitContext) VisitIterationBody(body *ast.Statement, visitor *ast.NodeV
 }
 
 func (c *EmitContext) VisitEmbeddedStatement(node *ast.Statement, visitor *ast.NodeVisitor) *ast.Statement {
-	embeddedStatement := visitor.VisitEmbeddedStatement(node)
-	if embeddedStatement == nil {
+	if node == nil {
 		return nil
 	}
-	if ast.IsNotEmittedStatement(embeddedStatement) {
+	embeddedStatement := visitor.VisitEmbeddedStatement(node)
+	if embeddedStatement == nil || ast.IsNotEmittedStatement(embeddedStatement) {
 		emptyStatement := visitor.Factory.NewEmptyStatement()
 		emptyStatement.Loc = node.Loc
 		c.SetOriginal(emptyStatement, node)

testdata/baselines/reference/compiler/typeOnlyExportAsIfBody.errors.txt

@@ -0,0 +1,8 @@
+typeOnlyExportAsIfBody.ts(1,11): error TS1233: An export declaration can only be used at the top level of a namespace or module.
+
+
+==== typeOnlyExportAsIfBody.ts (1 errors) ====
+    if (true) export type {};
+              ~~~~~~
+!!! error TS1233: An export declaration can only be used at the top level of a namespace or module.
+

testdata/baselines/reference/compiler/typeOnlyExportAsIfBody.js

@@ -0,0 +1,10 @@
+//// [tests/cases/compiler/typeOnlyExportAsIfBody.ts] ////
+
+//// [typeOnlyExportAsIfBody.ts]
+if (true) export type {};
+
+
+//// [typeOnlyExportAsIfBody.js]
+"use strict";
+if (true)
+    ;

testdata/baselines/reference/compiler/typeOnlyExportAsIfBody.symbols

@@ -0,0 +1,6 @@
+//// [tests/cases/compiler/typeOnlyExportAsIfBody.ts] ////
+
+=== typeOnlyExportAsIfBody.ts ===
+
+if (true) export type {};
+

testdata/baselines/reference/compiler/typeOnlyExportAsIfBody.types

@@ -0,0 +1,6 @@
+//// [tests/cases/compiler/typeOnlyExportAsIfBody.ts] ////
+
+=== typeOnlyExportAsIfBody.ts ===
+if (true) export type {};
+>true : true
+

testdata/tests/cases/compiler/typeOnlyExportAsIfBody.ts

@@ -0,0 +1,4 @@
+// @module: esnext
+// @moduleResolution: bundler
+
+if (true) export type {};