update_engine: Reflect ActionProcessor and UpdateBootFlags changes in AOSP

We changed the ActionProcessor interface and how we update boot flags in
CL:1065113 and CL:1011244. This patch reflects those changes in
update_attempter_android.*

BUG=chromium:807976
TEST=unittests
TEST=build and run in android

Change-Id: Ib06b6c1560e58771e66288208a525130a5811360
Reviewed-on: https://chromium-review.googlesource.com/1150737
Commit-Ready: Amin Hassani <ahassani@chromium.org>
Tested-by: Amin Hassani <ahassani@chromium.org>
Reviewed-by: Sen Jiang <senj@chromium.org>
diff --git a/Android.mk b/Android.mk
index 1f0397b..2fc6f46 100644
--- a/Android.mk
+++ b/Android.mk
@@ -421,6 +421,7 @@
     network_selector_android.cc \
     proxy_resolver.cc \
     update_attempter_android.cc \
+    update_boot_flags_action.cc \
     update_status_utils.cc \
     utils_android.cc
 include $(BUILD_STATIC_LIBRARY)
@@ -497,6 +498,7 @@
     proxy_resolver.cc \
     sideload_main.cc \
     update_attempter_android.cc \
+    update_boot_flags_action.cc \
     update_status_utils.cc \
     utils_android.cc
 LOCAL_STATIC_LIBRARIES := \