fix typo in DIGEST-MD5 charset

Fixes:32404412
Test: adb shell am instrument -w \
-e class com.android.phone.common.mail.store.imap.DigestMd5UtilsTest \
com.android.phone.tests/android.support.test.runner.AndroidJUnitRunner

Change-Id: If8c9f822d61e5091b0aaec00ef5fa8ab1596b86e
diff --git a/src/com/android/phone/common/mail/store/imap/DigestMd5Utils.java b/src/com/android/phone/common/mail/store/imap/DigestMd5Utils.java
index f78dbdf..436d03c 100644
--- a/src/com/android/phone/common/mail/store/imap/DigestMd5Utils.java
+++ b/src/com/android/phone/common/mail/store/imap/DigestMd5Utils.java
@@ -54,7 +54,7 @@
      */
     public static class Data {
 
-        private static final String CHARSET = "utf-8'";
+        private static final String CHARSET = "utf-8";
 
         public String username;
         public String password;
diff --git a/tests/src/com/android/phone/common/mail/store/imap/DigestMd5UtilsTest.java b/tests/src/com/android/phone/common/mail/store/imap/DigestMd5UtilsTest.java
index 5534632..81717a1 100644
--- a/tests/src/com/android/phone/common/mail/store/imap/DigestMd5UtilsTest.java
+++ b/tests/src/com/android/phone/common/mail/store/imap/DigestMd5UtilsTest.java
@@ -50,4 +50,24 @@
         assertEquals("ea40f60335c427b5527b84dbabcdfffd", response);
     }
 
+    public void testData_createResponse() {
+        DigestMd5Utils.Data data = new DigestMd5Utils.Data();
+        data.username = "chris";
+        data.password = "secret";
+        data.realm = "elwood.innosoft.com";
+        data.nonce = "OA6MG9tEQGm2hh";
+        data.cnonce = "OA6MHXh6VqTrRk";
+        data.nc = "00000001";
+        data.qop = "auth";
+        data.digestUri = "imap/elwood.innosoft.com";
+        assertEquals(data.createResponse(), "CHARSET=utf-8,"
+                + "username=\"chris\","
+                + "realm=\"elwood.innosoft.com\","
+                + "nonce=\"OA6MG9tEQGm2hh\","
+                + "nc=00000001,"
+                + "cnonce=\"OA6MHXh6VqTrRk\","
+                + "digest-uri=\"imap/elwood.innosoft.com\","
+                + "response=d388dad90d4bbd760a152321f2143af7,"
+                + "qop=auth");
+    }
 }