Revert "Revert "AU: do not copy filesystem during full updates""

This reverts commit d1cd325c3135d88498483da811b594ba6b91ce42

The problem that caused all autotests to fail with the original CL has now been rectified; lab devservers were updated to send the correct delta flag in their omaha response.

Change-Id: I664afb33f72856572baaa658cbd473c07271af36
Reviewed-on: https://gerrit.chromium.org/gerrit/56600
Reviewed-by: Gilad Arnold <garnold@chromium.org>
Tested-by: Gilad Arnold <garnold@chromium.org>
Commit-Queue: Gilad Arnold <garnold@chromium.org>
diff --git a/install_plan.h b/install_plan.h
index fc33f25..d6ff9e0 100644
--- a/install_plan.h
+++ b/install_plan.h
@@ -16,6 +16,7 @@
 
 struct InstallPlan {
   InstallPlan(bool is_resume,
+              bool is_full_update,
               const std::string& url,
               uint64_t payload_size,
               const std::string& payload_hash,
@@ -34,6 +35,7 @@
   void Dump() const;
 
   bool is_resume;
+  bool is_full_update;
   std::string download_url;  // url to download from
 
   uint64_t payload_size;                 // size of the payload