hwc: Delay HDMI/WFD connection request by one frame

  This change introduces hdmi pending state, where we allow
  frames to fall back to FB, closing all MDP pipes.

  Pipes could be used by primary (mixer 0) in which case moving
  them to external (mixer 1) involves unsetting them and setting
  them in the same round which is not recommended by the driver.
  It will fall back to GPU till HDMI is configured on a connect
  event.

  CRs-Fixed: 430057

Change-Id: I4b6677883c499f6d15656c3578190be1115ee6b4
diff --git a/libhwcomposer/hwc_utils.h b/libhwcomposer/hwc_utils.h
index f3a0fd6..14d4357 100644
--- a/libhwcomposer/hwc_utils.h
+++ b/libhwcomposer/hwc_utils.h
@@ -230,6 +230,8 @@
 
     //Securing in progress indicator
     bool mSecuring;
+    //External Display configuring progress indicator
+    bool mExtDispConfiguring;
     //Display in secure mode indicator
     bool mSecureMode;
     //Lock to prevent set from being called while blanking