Enable transpilation on SymbolTableTest.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=141892056

test/com/google/javascript/jscomp/SymbolTableTest.java

@@ -17,10 +17,12 @@
 package com.google.javascript.jscomp;
 
 import static com.google.common.truth.Truth.assertThat;
+import static com.google.javascript.jscomp.parsing.Config.JsDocParsing.INCLUDE_DESCRIPTIONS_NO_WHITESPACE;
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Ordering;
+import com.google.javascript.jscomp.CompilerOptions.LanguageMode;
 import com.google.javascript.jscomp.SymbolTable.Reference;
 import com.google.javascript.jscomp.SymbolTable.Symbol;
 import com.google.javascript.jscomp.SymbolTable.SymbolScope;
@@ -51,6 +53,8 @@ public void setUp() throws Exception {
     super.setUp();
 
     options = new CompilerOptions();
+    options.setLanguageIn(LanguageMode.ECMASCRIPT_NEXT);
+    options.setLanguageOut(LanguageMode.ECMASCRIPT5);
     options.setCodingConvention(new ClosureCodingConvention());
     CompilationLevel.SIMPLE_OPTIMIZATIONS.setOptionsForCompilationLevel(
         options);
@@ -59,7 +63,7 @@ public void setUp() throws Exception {
     options.setPreserveDetailedSourceInfo(true);
     options.setContinueAfterErrors(true);
     options.setAllowHotswapReplaceScript(true);
-    options.setParseJsDocDocumentation(true);
+    options.setParseJsDocDocumentation(INCLUDE_DESCRIPTIONS_NO_WHITESPACE);
   }
 
   public void testGlobalVar() throws Exception {