Created the dialog offering the user to merge their account data or keep it

chrome/android/java/src/org/chromium/chrome/browser/signin/SigninManager.java

Index: chrome/android/java/src/org/chromium/chrome/browser/signin/SigninManager.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/signin/SigninManager.java b/chrome/android/java/src/org/chromium/chrome/browser/signin/SigninManager.java
index 5d2bcd99193dba66e781bf2cc24ab0c85430129a..2a3a18a3f6f83ec2892e900cf5e6a9e8444520d9 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/signin/SigninManager.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/signin/SigninManager.java
@@ -23,7 +23,6 @@ import org.chromium.base.metrics.RecordHistogram;
 import org.chromium.base.metrics.RecordUserAction;
 import org.chromium.chrome.browser.externalauth.ExternalAuthUtils;
 import org.chromium.chrome.browser.externalauth.UserRecoverableErrorHandler;
-import org.chromium.signin.InvestigatedScenario;
 import org.chromium.sync.signin.AccountManagerHelper;
 import org.chromium.sync.signin.ChromeSigninController;
 
@@ -292,7 +291,7 @@ public class SigninManager implements AccountTrackerService.OnSystemAccountsSeed
     public void onSystemAccountsSeedingComplete() {
         if (mSignInState != null && mSignInState.blockedOnAccountSeeding) {
             mSignInState.blockedOnAccountSeeding = false;
-            progressSignInFlowInvestigateScenario();
+            progressSignInFlowCheckPolicy();
         }
     }
 
@@ -366,7 +365,7 @@ public class SigninManager implements AccountTrackerService.OnSystemAccountsSeed
 
     private void progressSignInFlowSeedSystemAccounts() {
         if (AccountTrackerService.get(mContext).checkAndSeedSystemAccounts()) {
-            progressSignInFlowInvestigateScenario();
+            progressSignInFlowCheckPolicy();
         } else if (AccountIdProvider.getInstance().canBeUsed(mContext)) {
             mSignInState.blockedOnAccountSeeding = true;
         } else {
@@ -381,11 +380,11 @@ public class SigninManager implements AccountTrackerService.OnSystemAccountsSeed
     }
 
     /**
-     * If sign-in is interactive and the user is changing accounts, display a confirmation dialog.
+     * Continues the signin flow by checking if there is a policy that the account is subject to.
      */
-    private void progressSignInFlowInvestigateScenario() {
-        if (!mSignInState.isInteractive()) {
-            progressSignInFlowCheckPolicy();
+    private void progressSignInFlowCheckPolicy() {
+        if (mSignInState == null) {
+            Log.w(TAG, "Ignoring sign in progress request as no pending sign in.");
             return;
         }
 
@@ -394,41 +393,6 @@ public class SigninManager implements AccountTrackerService.OnSystemAccountsSeed
             return;
         }
 
-        // TODO(skym): Warn for high risk upgrade scenario, crbug.com/572754.
-        if (SigninInvestigator.investigate(mSignInState.account.name)

[skym, 2016/02/26 20:22:57]

I'm concerned that by changing the ordering of the signin flow, you've
introduced an error. The signin investigator logic uses the account id/account
name mapping that is updated by the account seeding step. If you don't wait for
account seeding to complete, then your data is potentially invalid/stale.

[PEConn, 2016/03/03 18:23:25]

Can you expand on this? I can see that the signin investigator relies on
prefs::kGoogleServicesLastUsername and prefs::kGoogleServicesLastAccountId, but
I had assumed they wouldn't need updating during this flow.

[skym, 2016/03/03 18:54:51]

Sorry for not being very clear. The problem isn't the prefs, they don't involve
lookups. The problem is that SigninInvestigatorAndroid uses the
AccountTrackerService to get the GAIA id from the email for the account that's
currently being used to sign in. If we haven't ever seeded for this account,
then we fallback to email comparisons which could be wrong. If we haven't seeded
since this account's email address was changed, we potentially display the wrong
email in the warning message. If we haven't seeded since this account's email
address was change AND we don't have a last-signed-in-obfuscated-gaia-id
(legacy), our fallback to email comparison will use the wrong email.

-                == InvestigatedScenario.DIFFERENT_ACCOUNT) {
-            mSignInState.displayedDialog =
-                    ConfirmAccountChangeFragment.newInstance(mSignInState.account.name);
-            mSignInState.displayedDialog.show(
-                    mSignInState.activity.getFragmentManager(), CONFIRM_ACCOUNT_CHANGED_DIALOG_TAG);
-        } else {
-            // Do not display dialog, just sign-in.
-            progressSignInFlowCheckPolicy();
-        }
-    }
-
-    /**
-     * Called from ConfirmAccountChangeFragment if the new account name was confirmed.
-     */
-    void progressInteractiveSignInFlowAccountConfirmed() {
-        if (mSignInState == null || mSignInState.displayedDialog == null) {
-            // Stop if sign-in was cancelled or this is a duplicate click event.
-            return;
-        }
-        mSignInState.displayedDialog = null;
-
-        progressSignInFlowCheckPolicy();
-    }
-
-    /**
-     * Continues the signin flow by checking if there is a policy that the account is subject to.
-     */
-    private void progressSignInFlowCheckPolicy() {
-        if (mSignInState == null) {
-            Log.w(TAG, "Ignoring sign in progress request as no pending sign in.");
-            return;
-        }
-
         if (!nativeShouldLoadPolicyForUser(mSignInState.account.name)) {
             // Proceed with the sign-in flow without checking for policy if it can be determined
             // that this account can't have management enabled based on the username.
@@ -465,6 +429,7 @@ public class SigninManager implements AccountTrackerService.OnSystemAccountsSeed
             return;
         }
 
+        // TODO(peconn): Move this and other UI interactions into AccountSigninView.
         Log.d(TAG, "Account has policy management");
         mSignInState.displayedDialog = ConfirmManagedSigninFragment.newInstance(managementDomain);
         mSignInState.displayedDialog.show(