Do not ring in theater mode.

b/23979622

Change-Id: Ie08f04f12df144e68acac1972857037b14e57921
diff --git a/src/com/android/server/telecom/Ringer.java b/src/com/android/server/telecom/Ringer.java
index 99fb842..0245859 100644
--- a/src/com/android/server/telecom/Ringer.java
+++ b/src/com/android/server/telecom/Ringer.java
@@ -181,6 +181,11 @@
         Call foregroundCall = mCallsManager.getForegroundCall();
         Log.v(this, "startRingingOrCallWaiting, foregroundCall: %s.", foregroundCall);
 
+        if (Settings.Global.getInt(mContext.getContentResolver(), Settings.Global.THEATER_MODE_ON,
+                0) == 1) {
+            return;
+        }
+
         if (mRingingCalls.contains(foregroundCall)) {
             // The foreground call is one of incoming calls so play the ringer out loud.
             stopCallWaiting(call);