Temporary: set first slot color to NO_COLOR.

Due to change ag/575009, the SIM icon color will be used for the
InCallUI. We don't want the color to change for the single-SIM case, so
we set the first slot to NO_COLOR for now.

Bug: 17971273
Change-Id: I657326893a641cce3cdefb10f579d7f5260ce053
diff --git a/src/com/android/services/telephony/TelecomAccountRegistry.java b/src/com/android/services/telephony/TelecomAccountRegistry.java
index 6980df8..41eeb6e 100644
--- a/src/com/android/services/telephony/TelecomAccountRegistry.java
+++ b/src/com/android/services/telephony/TelecomAccountRegistry.java
@@ -123,8 +123,10 @@
                 if (record != null) {
                     subDisplayName = record.displayName;
                     slotId = record.slotId;
+
                     // Assign a "fake" color while the underlying Telephony stuff is refactored
-                    color = makeFakeColor(subId);
+                    // Assign PhoneAccount.NO_COLOR to first slot so single-SIM phones are unchanged
+                    color = slotId == 0? PhoneAccount.NO_COLOR : makeFakeColor(subId);
                 }
 
                 String slotIdString;