Remove onUpdate event + small changes

javascripts/background_scripts/reading_process.js

@@ -170,15 +170,10 @@ chrome.tabs.onActivated.addListener(function(activeInfo) {
   chrome.tabs.get(activeInfo.tabId, tabChange);
 });
 
-// When a tab's application changes, we have to message the proper operation
-// mode to the content script
-chrome.tabs.onUpdated.addListener(function(tabId, changeInfo, tab) {
-  tabChange(tab);
-});
-
 // Respond to every request to start the content script.
 chrome.runtime.onMessage.addListener(
   function(request, sender, sendResponse) {
-    if (request.greeting == "start_me")
-      sendResponse({farewell: "start"});
+    if (request.ask === "shouldStartPrivly?")
+      if(badgeText !== "off")
+        sendResponse({tell: "yes"});
   });

javascripts/content_scripts/privly.js

@@ -805,9 +805,10 @@ var privly = {
  * background script (reading_process.js) via a message  the current operating 
  * mode. If it receives confirmation, then privly.start() is called.
  */
-if (!privly.started) {
-  chrome.runtime.sendMessage({greeting: "start_me"}, function(response) {
-    if(response.farewell == 'start')
+if (chrome !== undefined && chrome.extension !== undefined && 
+      chrome.extension.sendMessage !== undefined && !privly.started) {
+  chrome.runtime.sendMessage({ask: "shouldStartPrivly?"}, function(response) {
+    if(response.tell === "yes")
       privly.start();
   });
 }