Unregister from network changes on destroy in ContextualSearchTabHelper

chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchTabHelper.java

Index: chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchTabHelper.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchTabHelper.java b/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchTabHelper.java
index 52ba3123426da05c4dfa8aec265c8640f16df656..f962737aee8cdfbc95961a207187d5dcfa753632 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchTabHelper.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/contextualsearch/ContextualSearchTabHelper.java
@@ -118,6 +118,9 @@ public class ContextualSearchTabHelper
         if (mTemplateUrlObserver != null) {
             TemplateUrlService.getInstance().removeObserver(mTemplateUrlObserver);
         }
+        if (NetworkChangeNotifier.isInitialized()) {
+            NetworkChangeNotifier.removeConnectionTypeObserver(this);
+        }
         removeContextualSearchHooks(mBaseContentViewCore);
         mBaseContentViewCore = null;
     }