commit f4da50937e1798a932b2e6e8bcab15cdf6fa4a93
author Deepanjan Roy <dproy@google.com> Wed Jul 15 17:59:04 2020 -0400
committer Deepanjan Roy <dproy@google.com> Wed Jul 15 17:59:04 2020 -0400
tree b5c1e09b82a539a22b0595c6ff21426dd743f0d6
parent ddc86ef759d8e5f1c46324aab820427a4a9e444d

metrics: Allow chrome metric protos to be compiled in

After this CL, we can add chrome metric protos to the metrics/chrome
directory. As an example, console error metric is checked in.

Previously, TraceMetrics and all its imports were being compiled to
protozero because it was part of ComputeMetricResult in
trace_processor.proto. However, we do not use the generated protozero
files anywhere, and it was preventing us from including the chrome
metrics because protozero struggled to process custom options. The
type of ComputeMetricResult.metrics has now been changed from
TraceMetrics to Bytes, so we do not have to generate any protozero code
for metrics. The UI can easily decode those bytes into TraceMetrics
proto if it has a TraceMetrics decoder.

All the chrome metrics will be listed in
metrics/chrome/all_chrome_metrics.proto. This file lists them as
extensions to TraceMetrics. We use metric extensions instead of directly
including them in TraceMetrics because it will make it simpler to copy
the metrics directly from chromium repo to perfetto in the future. To
prevent classes, we reserved extension range 1001 to 2000 for chrome
metrics in metrics.proto so there is no surprise clash.

Since we import custom_options.proto in all_chrome_metrics.proto, we
no longer need to generate binary descriptors for it separately.

Bug: 155480437
Change-Id: I5aba18984e272c0768830e619d158bf9fd11f9cc