inspect assignments to innerHTML

innerhtml-hook.js

/* inject via 

ppmm.loadFrameScript("data:,<js source>", true);
(where ppmm is the message manager, e.g. in shell.js)

framescript documentation explains why this works[1] and
the message manager docs[2] explain that the parent process
manager defined as ppmm in shell.js[3] can be used.

[1] https://developer.mozilla.org/en-US/Firefox/Multiprocess_Firefox/Frame_script_loading_and_lifetime
[2] https://developer.mozilla.org/en-US/Firefox/Multiprocess_Firefox/Message_Manager/Message_manager_overview
[3] https://dxr.mozilla.org/mozilla-central/source/b2g/chrome/content/shell.js

*/
(function () {
  var setter = Object.getOwnPropertyDescriptor(Element.prototype, 'innerHTML').set;
  Object.defineProperty(Element.prototype, 'innerHTML', {
    set: function innerHTML_Setter(val) {
      console.group();
      console.log('innerHTML on Object:', this, );
      console.log('Value:', JSON.stringify(val));
      var stack = new Error().stack;
      // Remove this function from the stack:
      stack = stack.trim().split('\n').slice(1).join(' <- ')
      console.log('Stack: ', stack)
      console.groupEnd();
      // call original innerHTML setter:
      return setter.call(this, val)     
    }
  });
});