Don't ignore errors in compiler.js --symbols-only

Previously we would report the error but then exit with 0.

Author: sbc100

src/jsifier.js

@@ -520,7 +520,9 @@ function ${name}(${args}) {
       includeFile('base64Utils.js');
     }
 
-    if (abortExecution) throw Error('Aborting compilation due to previous errors');
+    if (abortExecution) {
+      throw Error('Aborting compilation due to previous errors');
+    }
 
     // This is the main 'post' pass. Print out the generated code that we have here, together with the
     // rest of the output that we started to print out earlier (see comment on the
@@ -565,6 +567,9 @@ function ${name}(${args}) {
   }
 
   if (symbolsOnly) {
+    if (abortExecution) {
+      throw Error('Aborting compilation due to previous errors');
+    }
     print(JSON.stringify({
       deps: symbolDeps,
       asyncFuncs