Telephony: Remove references to mExitECMRunnable object.

Free mExitECMRunnable object while destroying CDMA phone.

Change-Id: I411b3e5e41a9cc76c3571a98f13f91d84523f623

telephony/java/com/android/internal/telephony/cdma/CDMAPhone.java

@@ -224,6 +224,7 @@ public class CDMAPhone extends PhoneBase {
             mCM.unregisterForNVReady(this); //EVENT_NV_READY
             mSST.unregisterForNetworkAttach(this); //EVENT_REGISTERED_TO_NETWORK
             mCM.unSetOnSuppServiceNotification(this);
+            removeCallbacks(mExitEcmRunnable);
 
             mPendingMmis.clear();
 
@@ -256,6 +257,7 @@ public class CDMAPhone extends PhoneBase {
             this.mSST = null;
             this.mEriManager = null;
             this.mCcatService = null;
+            this.mExitEcmRunnable = null;
     }
 
     protected void finalize() {