Update ActivityMonitor.onMatchIntent to ActivityMonitor.onStartActivity.

Bug: 37672383
Change-Id: I63adcafc6e8dced173d52f25e8a6521ae897c9aa
Test: builds

tests/app/src/com/android/settings/EncryptionInterstitialTest.java

@@ -93,7 +93,7 @@ public class EncryptionInterstitialTest {
         Intent mMatchedIntent = null;
 
         @Override
-        public ActivityResult onMatchIntent(Intent intent) {
+        public ActivityResult onStartActivity(Intent intent) {
             if ("test.unlock.intent".equals(intent.getAction())) {
                 mMatchedIntent = intent;
                 return new ActivityResult(Activity.RESULT_OK, null);