[NTP Snippets] SnippetsController cleanup: remove SigninStateObserver

chrome/android/javatests/src/org/chromium/chrome/browser/ChromeBackgroundServiceTest.java

Index: chrome/android/javatests/src/org/chromium/chrome/browser/ChromeBackgroundServiceTest.java
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/ChromeBackgroundServiceTest.java b/chrome/android/javatests/src/org/chromium/chrome/browser/ChromeBackgroundServiceTest.java
index d07b2bf26ce414b4f29b1656421cd347d16efe65..ad2c65f1865ba7f519a3e90e54d3a48eda34f0b7 100644
--- a/chrome/android/javatests/src/org/chromium/chrome/browser/ChromeBackgroundServiceTest.java
+++ b/chrome/android/javatests/src/org/chromium/chrome/browser/ChromeBackgroundServiceTest.java
@@ -72,10 +72,6 @@ public class ChromeBackgroundServiceTest extends InstrumentationTestCase {
     static class MockSnippetsController extends SnippetsController {
         private boolean mDidFetchSnippets = false;
 
-        MockSnippetsController() {
-            super(null);
-        }
-
         @Override
         public void fetchSnippets() {
             mDidFetchSnippets = true;