Add Installer.PayloadFormat metric

Adds a new PayloadFormat metric with three different values: Delta, Full
and ForcedFull. The metric is send whenever an update is applied successfully
indicating the type of the used payload. The difference between Full and
ForcedFull is that in the ForcedFull, the request sent to omaha included a
directive saying that a delta payload wasn't accepted, where a Full payload
is one where a delta payload was accepted but a Full payload was provided.

BUG=chromium:225977
TEST=cros_workon_make update_engine --test # Three tests added, one for each condition.

Change-Id: If44cd96df325d320ed327114cc5e5de3d34a5c62
Reviewed-on: https://gerrit.chromium.org/gerrit/60318
Reviewed-by: David Zeuthen <zeuthen@chromium.org>
Commit-Queue: Alex Deymo <deymo@chromium.org>
Tested-by: Alex Deymo <deymo@chromium.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/utils.h b/utils.h
index 0fe29487..bd4d2d60 100644
--- a/utils.h
+++ b/utils.h
@@ -168,6 +168,9 @@ std::string ToString(bool b);
 // Returns a string representation of the given enum.
 std::string ToString(DownloadSource source);
 
+// Returns a string representation of the given enum.
+std::string ToString(PayloadType payload_type);
+
 enum BootLoader {
   BootLoader_SYSLINUX = 0,
   BootLoader_CHROME_FIRMWARE = 1