Test block data polling on change

replmgr.js

Blockly.ReplMgr.pollYail = function() {
    
    console.log("Mark! pollYail ran\n");
    console.log(Blockly.mainWorkspace.getTopBlocks(false));

    try {
        if (window === undefined)    // If window is gone, then we are a zombie timer firing
            return;                  // in a destroyed frame.
    } catch (err) {                  // We get an error on FireFox when window is gone.
        return;
    }
    if (window.parent.ReplState.state == this.rsState.CONNECTED) {
        this.buildYail();
    }
    if (this.RefreshAssets === null) {
        try {
            this.RefreshAssets = window.parent.AssetManager_refreshAssets;
        } catch (err) {
        }
    }
    if (window.parent.ReplState.state == this.rsState.CONNECTED) {
        this.RefreshAssets(this.formName);
    }
};