Clear flags from inital install intent

Test: Tried to reproduce bug. With change bug cannot be reproduced anymore
Change-Id: I570a64fb56fecdffa9548d0783f88473c64a85c9
Fixes: 32623862
(cherry picked from commit dd868fe6f84a95295e23ebea806ecfba43ba6829)
diff --git a/src/com/android/packageinstaller/InstallStart.java b/src/com/android/packageinstaller/InstallStart.java
index b9de31c..6b7bf19 100644
--- a/src/com/android/packageinstaller/InstallStart.java
+++ b/src/com/android/packageinstaller/InstallStart.java
@@ -47,7 +47,7 @@
         int originatingUid = getOriginatingUid(sourceInfo);
 
         Intent nextActivity = new Intent(intent);
-        nextActivity.addFlags(Intent.FLAG_ACTIVITY_FORWARD_RESULT);
+        nextActivity.setFlags(Intent.FLAG_ACTIVITY_FORWARD_RESULT);
 
         // The the installation source as the nextActivity thinks this activity is the source, hence
         // set the originating UID and sourceInfo explicitly