code: function(mHarFileContent, aEntries, iIndex) {
  			var sUrlGroup = this.createUrlGroup(aEntries[iIndex].request.method, aEntries[iIndex].request.url);
  			var customGroupName = aEntries[iIndex]._customGroupName ? aEntries[iIndex]._customGroupName : this.sDefaultCustomGroup;
  			if (!mHarFileContent._groupedEntries[customGroupName]) {
  				mHarFileContent._groupedEntries[customGroupName] = {};
  			}
  			if (!mHarFileContent._groupedEntries[customGroupName][sUrlGroup]) {
  				mHarFileContent._groupedEntries[customGroupName][sUrlGroup] = [];
  			}
  			mHarFileContent._groupedEntries[customGroupName][sUrlGroup].push(iIndex);
  		}
docs: Adds an entry to the mapping. The order needs to be prepared and considered when adding the entry.
  This is used to add each entry from from a provided har file or to add an entry during runtime when play is already started.
  The mapping is created at 1st by a custom group, and 2nd the method and the URL (e.g. "GET/somePath/file.js").
  The custom group is optional and determined from a provided callback (e.g. It can determine the name of a test or
  can pop from an array of names).
  
  @param {object} mHarFileContent The har file content map.
  @param {array} aEntries The entries array. Default location of har files is within mHarFileContent.log.entries.
  @param {int} iIndex The index of the entry in the entries array. This is used as the key for the mapping.