Allow multiuser use of keystore

Since keystore has been refactored to let muliple users use it
simultaneously, we can remove all the restrictions put into place to
prevent it.

(cherry picked from commit cc48b0104e4d81592055a578a33f2a59f29bf907)

Bug: 7249554
Change-Id: I419474151380c29e49e50451befbbdf3af65b175
diff --git a/src/com/android/settings/CredentialStorage.java b/src/com/android/settings/CredentialStorage.java
index 1444a73..48c24f7 100644
--- a/src/com/android/settings/CredentialStorage.java
+++ b/src/com/android/settings/CredentialStorage.java
@@ -25,7 +25,6 @@
 import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.RemoteException;
-import android.os.UserHandle;
 import android.security.Credentials;
 import android.security.KeyChain.KeyChainConnection;
 import android.security.KeyChain;
@@ -109,12 +108,6 @@
     protected void onResume() {
         super.onResume();
 
-        if (UserHandle.myUserId() != UserHandle.USER_OWNER) {
-            Log.i(TAG, "Cannot install to CredentialStorage as non-primary user");
-            finish();
-            return;
-        }
-
         Intent intent = getIntent();
         String action = intent.getAction();
 
diff --git a/src/com/android/settings/SecuritySettings.java b/src/com/android/settings/SecuritySettings.java
index d75d630..556f548 100644
--- a/src/com/android/settings/SecuritySettings.java
+++ b/src/com/android/settings/SecuritySettings.java
@@ -234,21 +234,18 @@
         // Show password
         mShowPassword = (CheckBoxPreference) root.findPreference(KEY_SHOW_PASSWORD);
 
-        // Credential storage, only for primary user
-        if (mIsPrimary) {
-            mKeyStore = KeyStore.getInstance();
-            Preference credentialStorageType = root.findPreference(KEY_CREDENTIAL_STORAGE_TYPE);
+        // Credential storage
+        mKeyStore = KeyStore.getInstance();
+        Preference credentialStorageType = root.findPreference(KEY_CREDENTIAL_STORAGE_TYPE);
 
-            final int storageSummaryRes =
-                    mKeyStore.isHardwareBacked() ? R.string.credential_storage_type_hardware
-                            : R.string.credential_storage_type_software;
-            credentialStorageType.setSummary(storageSummaryRes);
+        final int storageSummaryRes =
+                mKeyStore.isHardwareBacked() ? R.string.credential_storage_type_hardware
+                        : R.string.credential_storage_type_software;
+        credentialStorageType.setSummary(storageSummaryRes);
 
-            mResetCredentials = root.findPreference(KEY_RESET_CREDENTIALS);
-        } else {
-            removePreference(KEY_CREDENTIALS_MANAGER);
-        }
+        mResetCredentials = root.findPreference(KEY_RESET_CREDENTIALS);
 
+        // Application install
         PreferenceGroup deviceAdminCategory= (PreferenceGroup)
                 root.findPreference(KEY_DEVICE_ADMIN_CATEGORY);
         mToggleAppInstallation = (CheckBoxPreference) findPreference(