Add support for perfetto::TraceConfig in tracing

Currently, the TraceConfig JSON object passed to the DevTools method to
start tracing only supports configuration of the Chrome-internal trace
event data source.

This commit provides additional parameters in DevTools:

- base64-encoded serialized protobuf message which takes precedence
  over other parameters,

- backend selection.

In order to handle new parameters, convert
base::trace_event::TraceConfig to perfetto::TraceConfig before passing
it and add support for the new perfettoConfig protocol param.

Add test to handle Command to run new test:
out/Default/content_browsertests --gtest_filter=DevToolsProtocolTest.TracingWithPerfettoConfig

Bug: chromium:1141381, chromium:1141386
Change-Id: I35e436487b2526bb3bf17bac34b9741712fb5319
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2560581
Commit-Queue: Eric Seckler <eseckler@chromium.org>
Reviewed-by: Andrey Kosyakov <caseq@chromium.org>
Reviewed-by: Eric Seckler <eseckler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836082}

content/browser/devtools/protocol/devtools_protocol_browsertest.cc

@@ -41,6 +41,7 @@
 #include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/security_style_explanations.h"
 #include "content/public/browser/ssl_status.h"
+#include "content/public/browser/tracing_controller.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/url_constants.h"
@@ -55,6 +56,7 @@
 #include "content/shell/browser/shell_browser_context.h"
 #include "content/shell/browser/shell_content_browser_client.h"
 #include "content/shell/browser/shell_download_manager_delegate.h"
+#include "services/tracing/public/cpp/perfetto/perfetto_config.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkColor.h"
@@ -2683,4 +2685,33 @@ IN_PROC_BROWSER_TEST_F(DevToolsDownloadContentTest, DISABLED_MultiDownload) {
       file2, GetTestFilePath("download", "download-test.lib")));
 }
 #endif  // !defined(ANDROID)
+
+IN_PROC_BROWSER_TEST_F(DevToolsProtocolTest, TracingWithPerfettoConfig) {
+  std::unique_ptr<base::DictionaryValue> params(new base::DictionaryValue());
+  base::trace_event::TraceConfig chrome_config;
+  base::DictionaryValue* command_result;
+  perfetto::TraceConfig perfetto_config;
+  std::string perfetto_config_encoded;
+
+  chrome_config = base::trace_event::TraceConfig();
+  perfetto_config = tracing::GetDefaultPerfettoConfig(
+      chrome_config,
+      /*privacy_filtering_enabled=*/false,
+      /*convert_to_legacy_json=*/false,
+      perfetto::protos::gen::ChromeConfig::USER_INITIATED);
+  base::Base64Encode(perfetto_config.SerializeAsString(),
+                     &perfetto_config_encoded);
+  params->SetKey("perfettoConfig", base::Value(perfetto_config_encoded));
+
+  NavigateToURLBlockUntilNavigationsComplete(shell(), GURL("about:blank"), 1);
+  Attach();
+
+  command_result = SendCommand("Tracing.start", std::move(params), true);
+  ASSERT_NE(command_result, nullptr);
+
+  command_result = SendCommand("Tracing.end", nullptr, true);
+  ASSERT_NE(command_result, nullptr);
+
+  WaitForNotification("Tracing.tracingComplete", true);
+}
 }  // namespace content

content/browser/devtools/protocol/tracing_handler.h

@@ -22,6 +22,7 @@
 #include "content/browser/devtools/protocol/tracing.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/tracing_controller.h"
+#include "services/tracing/public/cpp/perfetto/perfetto_config.h"
 
 namespace base {
 class RepeatingTimer;
@@ -69,6 +70,7 @@ class TracingHandler : public DevToolsDomainHandler, public Tracing::Backend {
              Maybe<std::string> transfer_format,
              Maybe<std::string> transfer_compression,
              Maybe<Tracing::TraceConfig> config,
+             Maybe<Binary> perfetto_config,
              std::unique_ptr<StartCallback> callback) override;
   Response End() override;
   void GetCategories(std::unique_ptr<GetCategoriesCallback> callback) override;
@@ -124,6 +126,8 @@ class TracingHandler : public DevToolsDomainHandler, public Tracing::Backend {
   CONTENT_EXPORT static base::trace_event::TraceConfig
       GetTraceConfigFromDevToolsConfig(
           const base::DictionaryValue& devtools_config);
+  perfetto::TraceConfig CreatePerfettoConfiguration(
+      const base::trace_event::TraceConfig& browser_config);
   void SetupProcessFilter(base::ProcessId gpu_pid, RenderFrameHost*);
   void StartTracingWithGpuPid(std::unique_ptr<StartCallback>,
                               base::ProcessId gpu_pid);
@@ -144,7 +148,7 @@ class TracingHandler : public DevToolsDomainHandler, public Tracing::Backend {
   TraceDataBufferState trace_data_buffer_state_;
   std::unique_ptr<DevToolsVideoConsumer> video_consumer_;
   int number_of_screenshots_from_video_consumer_ = 0;
-  base::trace_event::TraceConfig trace_config_;
+  perfetto::TraceConfig trace_config_;
   std::unique_ptr<TracingSession> session_;
   base::WeakPtrFactory<TracingHandler> weak_factory_{this};
 

third_party/blink/public/devtools_protocol/browser_protocol.pdl

@@ -8078,6 +8078,10 @@ experimental domain Tracing
       # transfer mode (defaults to `none`)
       optional StreamCompression streamCompression
       optional TraceConfig traceConfig
+      # Base64-encoded serialized perfetto.protos.TraceConfig protobuf message
+      # When specified, the parameters `categories`, `options`, `traceConfig`
+      # are ignored.
+      optional binary perfettoConfig
 
   event bufferUsage
     parameters