code: function initializeSession(editor, previousEditor) {
              session = new Session(editor);
              ScopeManager.handleEditorChange(session, editor.document,
                  previousEditor ? previousEditor.document : null);
              phProvider.setSession(session);
              cachedHints = null;
          }
docs: /*
  When the editor is changed, reset the hinting session and cached
  information, and reject any pending deferred requests.
  
  @param {!Editor} editor - editor context to be initialized.
  @param {?Editor} previousEditor - the previous editor.