add default debug log objects for tests

packages/core/core/src/events.ts

@@ -59,6 +59,12 @@ export class EmbarkEmitter extends EventEmitter {
     super();
     if (options) {
       this.debugLog = options.debugLog;
+    } else {
+      this.debugLog = {
+        log: () => {},
+        getStackTrace: () => { return ""; },
+        isEnabled: () => { return false; }
+      };
     }
   }
 

packages/core/typings/src/embark.d.ts

@@ -73,6 +73,7 @@ export interface Embark {
   fs: any;
   config: Config;
   currentContext: string[];
+  logId: any;
   registerActionForEvent(
     name: string,
     action: (params: any, cb: (error: any, result: any) => void) => void,

packages/embark/src/lib/core/plugins.js

@@ -17,6 +17,15 @@ var Plugins = function(options) {
   this.fs = fs;
   this.env = options.env;
   this.version = options.version;
+
+  if (!this.debugLog) {
+    this.debugLog = {
+      log: () => { },
+      moduleInit: () => { return ""; },
+      getStackTrace: () => { return ""; },
+      isEnabled: () => { return false; }
+    };
+  }
 };
 
 Plugins.deprecated = {