Fix assumption about GCM in prefetch java tests

We were assuming that there is only GCM subtype in play, but this assumption
will not hold soon. This change gets the gcm authorization for the prefetch
subtype explicitly.

This change should unblock
https://chromium-review.googlesource.com/c/chromium/src/+/1695346

Change-Id: I275aaeea6c43ee027130c9dbdc0ba10bed698555
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1699369Reviewed-by: Jian Li <jianli@chromium.org>
Commit-Queue: Dan H <harringtond@chromium.org>
Cr-Commit-Position: refs/heads/master@{#677085}

chrome/android/javatests/src/org/chromium/chrome/browser/offlinepages/prefetch/TestOfflinePageService.java

@@ -7,7 +7,6 @@ package org.chromium.chrome.browser.offlinepages.prefetch;
 import android.content.Context;
 import android.os.Bundle;
 import android.support.test.InstrumentationRegistry;
-import android.util.Pair;
 
 import com.google.protobuf.InvalidProtocolBufferException;
 
@@ -265,19 +264,18 @@ public class TestOfflinePageService {
         synchronized (mIncompleteOperations) {
             operationName = mIncompleteOperations.remove(0);
         }
+        final String prefetchSubtype = "com.google.chrome.OfflinePagePrefetch";
         // We have to wait until Chrome gets the GCM token.
         CriteriaHelper.pollInstrumentationThread(() -> {
             try {
-                FakeInstanceIDWithSubtype.getSubtypeAndAuthorizedEntityOfOnlyToken();
+                FakeInstanceIDWithSubtype.getAuthorizedEntityForSubtype(prefetchSubtype);
                 return true;
             } catch (IllegalStateException e) {
                 return false;
             }
         }, "GetGCMToken not complete", 15000, 500);
-        final Pair<String, String> appIdAndSenderId =
-                FakeInstanceIDWithSubtype.getSubtypeAndAuthorizedEntityOfOnlyToken();
-        final String appId = appIdAndSenderId.first;
-        final String senderId = appIdAndSenderId.second;
+        final String senderId =
+                FakeInstanceIDWithSubtype.getAuthorizedEntityForSubtype(prefetchSubtype);
         TestThreadUtils.runOnUiThreadBlocking(() -> {
             Context context = InstrumentationRegistry.getInstrumentation()
                                       .getTargetContext()
@@ -285,7 +283,7 @@ public class TestOfflinePageService {
 
             Bundle extras = new Bundle();
             extras.putString("pageBundle", operationName);
-            extras.putString("subtype", appId); // is this necessary?
+            extras.putString("subtype", prefetchSubtype); // is this necessary?
 
             GCMMessage message = new GCMMessage(senderId, extras);
             try {

components/gcm_driver/instance_id/android/javatests/src/org/chromium/components/gcm_driver/instance_id/FakeInstanceIDWithSubtype.java

@@ -67,14 +67,27 @@ public class FakeInstanceIDWithSubtype extends InstanceIDWithSubtype {
                 throw new IllegalStateException("Expected exactly one InstanceID, but there are "
                         + sSubtypeInstances.size());
             }
+            final String subType = sSubtypeInstances.values().iterator().next().getSubtype();
+            return Pair.create(subType, getAuthorizedEntityForSubtype(subType));
+        }
+    }
+
+    /**
+     * If an instanceID exists for subtype, and it has exactly one token, this returns
+     * the authorizedEntity of the token. Otherwise it throws.
+     */
+    public static String getAuthorizedEntityForSubtype(String subtype) {
+        synchronized (sSubtypeInstancesLock) {
             FakeInstanceIDWithSubtype iid =
-                    (FakeInstanceIDWithSubtype) sSubtypeInstances.values().iterator().next();
+                    (FakeInstanceIDWithSubtype) sSubtypeInstances.get(subtype);
+            if (iid == null) {
+                throw new IllegalStateException("No subtype instance found for " + subtype);
+            }
             if (iid.mTokens.size() != 1) {
                 throw new IllegalStateException(
                         "Expected exactly one token, but there are " + iid.mTokens.size());
             }
-            String authorizedEntity = iid.mTokens.keySet().iterator().next().split(",", 3)[1];
-            return Pair.create(iid.getSubtype(), authorizedEntity);
+            return iid.mTokens.keySet().iterator().next().split(",", 3)[1];
         }
     }