[PostBoot] Fix bug where post boot shader has a flicker

Pass correct default value -1 when getting RUNTIME_STATE_PENDING_REQUEST_CODE when it is not set.

This will avoid accidentally starting ProxyActivityStarter from Launcher#onCreate(), which will cause a flicker for post boot animation

Fix: 375308654
Flag: NONE - xml flag not supported
Test: manual
Change-Id: Ic3888508657b5b7aab37f6022768d53007bf9c00
diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index a8840fe..893b7e0 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -1344,7 +1344,8 @@
         if (requestArgs != null) {
             setWaitingForResult(requestArgs);
         }
-        mPendingActivityRequestCode = savedState.getInt(RUNTIME_STATE_PENDING_REQUEST_CODE);
+        mPendingActivityRequestCode = savedState.getInt(
+                RUNTIME_STATE_PENDING_REQUEST_CODE, mPendingActivityRequestCode);
 
         mPendingActivityResult = savedState.getParcelable(RUNTIME_STATE_PENDING_ACTIVITY_RESULT);