[Offline pages] Addressing several reload snackbar issues

chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageUtils.java

Index: chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageUtils.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageUtils.java b/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageUtils.java
index 6825413bc06587f834fca0a20f701e788fc77156..da4b9163a6744c972e380ef9affb974ccee23ff8 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageUtils.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/OfflinePageUtils.java
@@ -161,7 +161,9 @@ public class OfflinePageUtils {
      * @param tab The current tab.
      */
     public static void showOfflineSnackbarIfNecessary(ChromeActivity activity, Tab tab) {
-        if (OfflinePageTabObserver.getInstance() == null) {
+        if (OfflinePageTabObserver.getInstance() == null
+                || !OfflinePageTabObserver.getInstance().isCurrentContext(
+                           activity.getBaseContext())) {
             SnackbarController snackbarController =
                     createReloadSnackbarController(activity.getTabModelSelector());
             OfflinePageTabObserver.init(