Fix NPE during activity recreation

Bug: 13630676
Change-Id: I3b68d5f21a4b77eab5b5493dcde670ad08cdc372
diff --git a/src/com/android/dialer/DialtactsActivity.java b/src/com/android/dialer/DialtactsActivity.java
index 363adda..32a22c9 100644
--- a/src/com/android/dialer/DialtactsActivity.java
+++ b/src/com/android/dialer/DialtactsActivity.java
@@ -970,7 +970,9 @@
 
     @Override
     public void setDialButtonEnabled(boolean enabled) {
-        mDialButton.setEnabled(enabled);
+        if (mDialButton != null) {
+            mDialButton.setEnabled(enabled);
+        }
     }
 
     @Override
diff --git a/src/com/android/dialer/dialpad/DialpadFragment.java b/src/com/android/dialer/dialpad/DialpadFragment.java
index 2d3c0ee..36d5cf8 100644
--- a/src/com/android/dialer/dialpad/DialpadFragment.java
+++ b/src/com/android/dialer/dialpad/DialpadFragment.java
@@ -1567,6 +1567,9 @@
      * Update the enabledness of the "Dial" and "Backspace" buttons if applicable.
      */
     private void updateDialAndDeleteButtonEnabledState() {
+        if (getActivity() == null) {
+            return;
+        }
         final boolean digitsNotEmpty = !isDigitsEmpty();
         mDelete.setEnabled(digitsNotEmpty);
         // On CDMA phones, if we're already on a call, we *always* enable the Dial button (since