Remove all uses of deprecated API in Support13Demos.

Bug: 31017538
Change-Id: I03cdbe60220f62ccc6fd90d080785d86b315f44a
diff --git a/samples/Support13Demos/src/com/example/android/supportv13/app/ActionBarTabsPager.java b/samples/Support13Demos/src/com/example/android/supportv13/app/ActionBarTabsPager.java
index 301a2f8..1bf7691 100644
--- a/samples/Support13Demos/src/com/example/android/supportv13/app/ActionBarTabsPager.java
+++ b/samples/Support13Demos/src/com/example/android/supportv13/app/ActionBarTabsPager.java
@@ -103,7 +103,7 @@
             mActionBar = activity.getActionBar();
             mViewPager = pager;
             mViewPager.setAdapter(this);
-            mViewPager.setOnPageChangeListener(this);
+            mViewPager.addOnPageChangeListener(this);
         }
 
         public void addTab(ActionBar.Tab tab, Class<?> clss, Bundle args) {
diff --git a/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentNestingPagerSupport.java b/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentNestingPagerSupport.java
index 0a88a05..3896d9a 100644
--- a/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentNestingPagerSupport.java
+++ b/samples/Support13Demos/src/com/example/android/supportv13/app/FragmentNestingPagerSupport.java
@@ -101,7 +101,7 @@
             mActionBar = activity.getActionBar();
             mViewPager = pager;
             mViewPager.setAdapter(this);
-            mViewPager.setOnPageChangeListener(this);
+            mViewPager.addOnPageChangeListener(this);
         }
 
         public void addTab(ActionBar.Tab tab, Class<?> clss, Bundle args) {
diff --git a/samples/Support4Demos/src/com/example/android/supportv4/app/FragmentTabsPager.java b/samples/Support4Demos/src/com/example/android/supportv4/app/FragmentTabsPager.java
index cf734d7..2cd3ac8 100644
--- a/samples/Support4Demos/src/com/example/android/supportv4/app/FragmentTabsPager.java
+++ b/samples/Support4Demos/src/com/example/android/supportv4/app/FragmentTabsPager.java
@@ -125,7 +125,7 @@
             mViewPager = pager;
             mTabHost.setOnTabChangedListener(this);
             mViewPager.setAdapter(this);
-            mViewPager.setOnPageChangeListener(this);
+            mViewPager.addOnPageChangeListener(this);
         }
 
         public void addTab(TabHost.TabSpec tabSpec, Class<?> clss, Bundle args) {