setSelectedHeader() when switching to fragment

Without this change, passing a EXTRA_SHOW_FRAGMENT value
for a two panel preferences activity will cause the correct
fragment to be shown. However, it will not cause the
correct header to be highlighted.

Bug: 15675746
Bug: 5045558
Change-Id: I18d8e15dd104e8f39ae1ccbb11ab17fd1bf7462e

core/java/android/preference/PreferenceActivity.java

@@ -1194,7 +1194,14 @@ public abstract class PreferenceActivity extends ListActivity implements
      * @param args Optional arguments to supply to the fragment.
      */
     public void switchToHeader(String fragmentName, Bundle args) {
-        setSelectedHeader(null);
+        Header selectedHeader = null;
+        for (int i = 0; i < mHeaders.size(); i++) {
+            if (fragmentName.equals(mHeaders.get(i).fragment)) {
+                selectedHeader = mHeaders.get(i);
+                break;
+            }
+        }
+        setSelectedHeader(selectedHeader);
         switchToHeaderInner(fragmentName, args);
     }