Add the UI for the Interests Prototype.

chrome/android/java/src/org/chromium/chrome/browser/ntp/InterestsService.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/InterestsService.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/InterestsService.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/InterestsService.java
index 418fa924cf92d40a57a72055b89f342f7f6b8333..736d6e495d605a9bdf75392d7e26a62aed5e2b17 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/InterestsService.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/InterestsService.java
@@ -11,6 +11,9 @@ import org.chromium.chrome.browser.profiles.Profile;
  * Retrieve the user's interests.
  */
 public class InterestsService {
+    public static final String AUTH_SCOPE =
+            "https://www.googleapis.com/auth/googlenow";

[Marc Treib, 2015/09/18 13:26:04]

Hm. Shouldn't the InterestsService itself (probably the native version) be
responsible for fetching a properly-scoped access token, given a signed-in
profile?

[tache, 2015/09/21 15:35:55]

I don't think so. Looking at the OAuth2TokenService (java) it uses the android
AccountManager. This allows it to show popups / notifications asking for the
user's permission.

I assume that how you get a valid token is platform specific and thus the
InterestsFetcher shouldn't be responsible for it.

I could move the AUTH_SCOPE to the native part and exposes through JNI to Java.

[Marc Treib, 2015/09/21 16:20:08]

The native ProfileOAuth2TokenService works on all platforms, it has some
platform-specific implementation parts I think (which for Android probably
forward to the Java one).
You can look at PermissionRequestCreatorApiary for an example.
Nah, if it's only used in Java, then that's where it should live.

+
     private long mNativeInterestsService;
 
     /**