String concatentation errors suck!

shitty-strings.js

var script = document.createElement('script');
script.innerHTML = 
  'if (window.top !== window) {                                            '+
  '  var subFrame = document.createElement("script");                      '+
  '  subFrame.src = "'+chrome.extension.getURL('specific/sub_frame.js')+'";'+
  '  document.documentElement.appendChild(subFrame); '
  '}';
document.documentElement.appendChild(script);

//gives "unexpected end of input", with no line numbers!

someStyleElement.innerHTML = 
  'html {display: none; /*trolling*/}' +
  +'div {display: block !important; }'
  +'foo{color: black;}';

//Silently gives: "html {display: none; /*trolling*/}NaNfoo{color: black;}" FARDGE!