userdebug: support perfetto traces as a section in incident reports

This set of patches adds a way for the perfetto command line client to
save a trace to a hardcoded location,
/data/misc/perfetto-traces/incident-trace, and call into incidentd to
start a report, which will include said trace in a new section.

This is not a long-term solution, and is structured to minimize changes
to perfetto and incidentd. The latter is currently architected in a way
where it can only pull pre-defined information out of the system, so
we're resorting to persisting the intermediate results in a hardcoded
location.

This will introduce at most two more linked files at the same time.

Bug: 130543265
Tested: manually on blueline-userdebug
Change-Id: Iaaa312d2d9da73ca329807211227a8c7a049102c

cmds/incident_helper/src/main.cpp

@@ -72,6 +72,8 @@ static TextParserBase* selectParser(int section) {
             return new PsParser();
         case 2006:
             return new BatteryTypeParser();
+        case 3026: // system_trace is already a serialized protobuf
+            return new NoopParser();
         default:
             // Return no op parser when no specific ones are implemented.
             return new NoopParser();

cmds/incidentd/src/Section.cpp

@@ -67,6 +67,8 @@ bool section_requires_specific_mention(int sectionId) {
     switch (sectionId) {
         case 3025: // restricted_images
             return true;
+        case 3026: // system_trace
+            return true;
         default:
             return false;
     }

core/proto/android/os/incident.proto

@@ -321,6 +321,14 @@ message IncidentProto {
         (section).args = "incidentcompanion --restricted_image"
     ];
 
+    // System trace as a serialized protobuf.
+    optional bytes system_trace = 3026 [
+        (section).type = SECTION_FILE,
+        (section).args = "/data/misc/perfetto-traces/incident-trace",
+        (privacy).dest = DEST_AUTOMATIC,
+        (section).userdebug_and_eng_only = true
+    ];
+
     // Reserved for OEMs.
     extensions 50000 to 100000;
 }

tools/incident_section_gen/main.cpp

@@ -408,9 +408,10 @@ static bool generateSectionListCpp(Descriptor const* descriptor) {
     for (int i=0; i<descriptor->field_count(); i++) {
         const FieldDescriptor* field = descriptor->field(i);
 
-        if (field->type() != FieldDescriptor::TYPE_MESSAGE
-                && field->type() != FieldDescriptor::TYPE_STRING) {
-            continue;
+        if (field->type() != FieldDescriptor::TYPE_MESSAGE &&
+            field->type() != FieldDescriptor::TYPE_STRING &&
+            field->type() != FieldDescriptor::TYPE_BYTES) {
+          continue;
         }
 
         const SectionFlags s = getSectionFlags(field);