Adding check in when getting current tab tag to prevent crash/NPE. (Bug: 5492469)

Change-Id: I51960bafbf1a9b2201639fb34786a7415e1e57dd
diff --git a/src/com/android/launcher2/AppsCustomizePagedView.java b/src/com/android/launcher2/AppsCustomizePagedView.java
index 4103141..d8ff73c 100644
--- a/src/com/android/launcher2/AppsCustomizePagedView.java
+++ b/src/com/android/launcher2/AppsCustomizePagedView.java
@@ -643,12 +643,14 @@
     private void updateCurrentTab(int currentPage) {
         AppsCustomizeTabHost tabHost = getTabHost();
         String tag = tabHost.getCurrentTabTag();
-        if (currentPage >= mNumAppsPages &&
-                !tag.equals(tabHost.getTabTagForContentType(ContentType.Widgets))) {
-            tabHost.setCurrentTabFromContent(ContentType.Widgets);
-        } else if (currentPage < mNumAppsPages &&
-                !tag.equals(tabHost.getTabTagForContentType(ContentType.Applications))) {
-            tabHost.setCurrentTabFromContent(ContentType.Applications);
+        if (tag != null) {
+            if (currentPage >= mNumAppsPages &&
+                    !tag.equals(tabHost.getTabTagForContentType(ContentType.Widgets))) {
+                tabHost.setCurrentTabFromContent(ContentType.Widgets);
+            } else if (currentPage < mNumAppsPages &&
+                    !tag.equals(tabHost.getTabTagForContentType(ContentType.Applications))) {
+                tabHost.setCurrentTabFromContent(ContentType.Applications);
+            }
         }
     }
 
@@ -1367,8 +1369,10 @@
     public void reset() {
         AppsCustomizeTabHost tabHost = getTabHost();
         String tag = tabHost.getCurrentTabTag();
-        if (!tag.equals(tabHost.getTabTagForContentType(ContentType.Applications))) {
-            tabHost.setCurrentTabFromContent(ContentType.Applications);
+        if (tag != null) {
+            if (!tag.equals(tabHost.getTabTagForContentType(ContentType.Applications))) {
+                tabHost.setCurrentTabFromContent(ContentType.Applications);
+            }
         }
         if (mCurrentPage != 0) {
             invalidatePageData(0);