Fix the sourcemap emit of lambda expression without return on another line

Handles #5122

Author: sheetalkamat

src/compiler/emitter.ts

@@ -5003,8 +5003,10 @@ var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, Promi
                     increaseIndent();
                     writeLine();
                     emitLeadingComments(node.body);
+                    emitStart(body);
                     write("return ");
                     emit(body);
+                    emitEnd(body);
                     write(";");
                     emitTrailingComments(node.body);
 

tests/baselines/reference/sourceMapValidationLambdaSpanningMultipleLines.js.map

@@ -24,13 +24,16 @@ sourceFile:sourceMapValidationLambdaSpanningMultipleLines.ts
 4 >Emitted(1, 16) Source(1, 15) + SourceIndex(0)
 ---
 >>>    return item;
-1->^^^^^^^^^^^
-2 >           ^^^^
+1->^^^^
+2 >    ^^^^^^^
+3 >           ^^^^
 1->) =>
   >    
-2 >           item
-1->Emitted(2, 12) Source(2, 5) + SourceIndex(0)
-2 >Emitted(2, 16) Source(2, 9) + SourceIndex(0)
+2 >    
+3 >           item
+1->Emitted(2, 5) Source(2, 5) + SourceIndex(0)
+2 >Emitted(2, 12) Source(2, 5) + SourceIndex(0)
+3 >Emitted(2, 16) Source(2, 9) + SourceIndex(0)
 ---
 >>>});
 1 >