[perf] Add more C++ traces to WebView startup

This change adds more tracing statements to the WebView startup code.

Bug: 1019793
Test: trace output has new blocks
Change-Id: Ic401ace0999f15456d62e69cc13bdabca05241b1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2083740Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Reviewed-by: Bo <boliu@chromium.org>
Reviewed-by: Changwan Ryu <changwan@chromium.org>
Commit-Queue: Oksana Zhuravlova <oksamyt@chromium.org>
Cr-Commit-Position: refs/heads/master@{#747573}

android_webview/browser/aw_browser_context.cc

@@ -79,6 +79,7 @@ bool IgnoreOriginSecurityCheck(const GURL& url) {
 
 void MigrateProfileData(base::FilePath cache_path,
                         base::FilePath context_storage_path) {
+  TRACE_EVENT0("startup", "MigrateProfileData");
   FilePath old_cache_path;
   base::PathService::Get(base::DIR_CACHE, &old_cache_path);
   old_cache_path = old_cache_path.DirName().Append(
@@ -142,6 +143,8 @@ AwBrowserContext::AwBrowserContext()
       simple_factory_key_(GetPath(), IsOffTheRecord()) {
   DCHECK(!g_browser_context);
 
+  TRACE_EVENT0("startup", "AwBrowserContext::AwBrowserContext");
+
   if (IsDefaultBrowserContext()) {
     MigrateProfileData(GetCacheDir(), GetContextStoragePath());
   }
@@ -253,6 +256,7 @@ void AwBrowserContext::RegisterPrefs(PrefRegistrySimple* registry) {
 }
 
 void AwBrowserContext::CreateUserPrefService() {
+  TRACE_EVENT0("startup", "AwBrowserContext::CreateUserPrefService");
   auto pref_registry = base::MakeRefCounted<user_prefs::PrefRegistrySyncable>();
 
   RegisterPrefs(pref_registry.get());

android_webview/browser/aw_browser_main_parts.cc

@@ -121,6 +121,7 @@ int AwBrowserMainParts::PreCreateThreads() {
 }
 
 void AwBrowserMainParts::PreMainMessageLoopRun() {
+  TRACE_EVENT0("startup", "AwBrowserMainParts::PreMainMessageLoopRun");
   AwBrowserProcess::GetInstance()->PreMainMessageLoopRun();
   browser_client_->InitBrowserContext();
   content::WebUIControllerFactory::RegisterFactory(

android_webview/lib/aw_main_delegate.cc

@@ -75,6 +75,7 @@ AwMainDelegate::AwMainDelegate() = default;
 AwMainDelegate::~AwMainDelegate() = default;
 
 bool AwMainDelegate::BasicStartupComplete(int* exit_code) {
+  TRACE_EVENT0("startup", "AwMainDelegate::BasicStartupComplete");
   base::CommandLine* cl = base::CommandLine::ForCurrentProcess();
 
   // WebView uses the Android system's scrollbars and overscroll glow.
@@ -247,6 +248,7 @@ bool AwMainDelegate::BasicStartupComplete(int* exit_code) {
 }
 
 void AwMainDelegate::PreSandboxStartup() {
+  TRACE_EVENT0("startup", "AwMainDelegate::PreSandboxStartup");
 #if defined(ARCH_CPU_ARM_FAMILY)
   // Create an instance of the CPU class to parse /proc/cpuinfo and cache
   // cpu_brand info.

components/visitedlink/browser/visitedlink_writer.cc

@@ -263,6 +263,7 @@ VisitedLinkWriter::~VisitedLinkWriter() {
 }
 
 bool VisitedLinkWriter::Init() {
+  TRACE_EVENT0("browser", "VisitedLinkWriter::Init");
   // Create the temporary table. If the table is rebuilt that temporary table
   // will be became the main table.
   // The salt must be generated before the table so that it can be copied to

content/app/content_main_runner_impl.cc

@@ -735,6 +735,7 @@ int ContentMainRunnerImpl::Initialize(const ContentMainParams& params) {
     // file is available we have to apply it _before_ the main ICU data file.
     // Otherwise, the languages of the extra ICU file will be overridden.
     if (process_type.empty()) {
+      TRACE_EVENT0("startup", "InitializeICU");
       // In browser process load ICU data files from disk.
       if (GetContentClient()->browser()->ShouldLoadExtraIcuDataFile()) {
         if (!base::i18n::InitializeExtraICU()) {

content/public/android/java/src/org/chromium/content/browser/BrowserStartupControllerImpl.java

@@ -21,6 +21,7 @@ import org.chromium.base.library_loader.LibraryLoader;
 import org.chromium.base.library_loader.LibraryProcessType;
 import org.chromium.base.library_loader.LoaderErrors;
 import org.chromium.base.library_loader.ProcessInitException;
+import org.chromium.base.metrics.ScopedSysTraceEvent;
 import org.chromium.base.task.PostTask;
 import org.chromium.content.app.ContentMain;
 import org.chromium.content.browser.ServicificationStartupUma.ServicificationStartup;
@@ -245,7 +246,10 @@ public class BrowserStartupControllerImpl implements BrowserStartupController {
         // If already started skip to checking the result
         if (!mFullBrowserStartupDone) {
             if (!mHasStartedInitializingBrowserProcess || !mPostResourceExtractionTasksCompleted) {
-                prepareToStartBrowserProcess(singleProcess, null);
+                try (ScopedSysTraceEvent e2 = ScopedSysTraceEvent.scoped(
+                             "BrowserStartupController.prepareToStartBrowserProcess")) {
+                    prepareToStartBrowserProcess(singleProcess, null);
+                }
             }
 
             boolean startedSuccessfully = true;