Fix Policy-related unit tests (proguard flags)

Bug: 4482579
Change-Id: I321017016a39dc36dea83895c95b6acdb735bf1e
diff --git a/proguard.flags b/proguard.flags
index 6d282bd..d60389d 100644
--- a/proguard.flags
+++ b/proguard.flags
@@ -176,6 +176,15 @@
 
 -keepclasseswithmembers class com.android.emailcommon.provider.EmailContent$Account {
   *** getShortcutSafeUri();
+  *** refresh(android.content.Context);
+}
+
+-keepclasseswithmembers class com.android.emailcommon.provider.Policy {
+  *** setAttachmentFlagsForNewPolicy(android.content.Context,
+    com.android.emailcommon.provider.EmailContent$Account,
+    com.android.emailcommon.provider.Policy);
+  *** clearAccountPolicy(android.content.Context,
+    com.android.emailcommon.provider.EmailContent$Account);
 }
 
 -keep class org.apache.james.mime4j.field.Field {