Parse multiple packages from Omaha response.
The multi-payload info are stored in OmahaResponse and InstallPlan, but
we still can only apply the first payload for now.
Bug: 36252799
Test: mma -j
Test: update_engine_unittests
Change-Id: I5ca63944ae9082670d0e67888409374f140d4245
(cherry picked from commit 2aba8a87d4fac245a2e2d238b3159f8eabce630f)
diff --git a/common/constants.cc b/common/constants.cc
index 88d0445..c0a6e27 100644
--- a/common/constants.cc
+++ b/common/constants.cc
@@ -78,6 +78,7 @@
const char kPrefsUpdateStateNextDataLength[] = "update-state-next-data-length";
const char kPrefsUpdateStateNextDataOffset[] = "update-state-next-data-offset";
const char kPrefsUpdateStateNextOperation[] = "update-state-next-operation";
+const char kPrefsUpdateStatePayloadIndex[] = "update-state-payload-index";
const char kPrefsUpdateStateSHA256Context[] = "update-state-sha-256-context";
const char kPrefsUpdateStateSignatureBlob[] = "update-state-signature-blob";
const char kPrefsUpdateStateSignedSHA256Context[] =