[ChromeDriver] Expose CPU Profiling DevTools API into chromeWebDriver

chrome/test/chromedriver/chrome/cpu_profile.cc

Index: chrome/test/chromedriver/chrome/cpu_profile.cc
diff --git a/chrome/test/chromedriver/chrome/cpu_profile.cc b/chrome/test/chromedriver/chrome/cpu_profile.cc
new file mode 100644
index 0000000000000000000000000000000000000000..6a003ca8f14d553562ddce60a14f59766e17cf7f
--- /dev/null
+++ b/chrome/test/chromedriver/chrome/cpu_profile.cc
@@ -0,0 +1,74 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/test/chromedriver/chrome/cpu_profile.h"
+
+#include "base/json/json_reader.h"
+#include "base/logging.h"
+#include "base/values.h"
+#include "chrome/test/chromedriver/chrome/devtools_client.h"
+
+CpuProfile::CpuProfile(DevToolsClient* client)
+    : client_(client) {
+  client_->AddListener(this);

[klm, 2014/05/10 02:21:57]

Why do we need to be a listener at all, if our OnEvent is a no-op?

+}
+
+CpuProfile::~CpuProfile() {}
+
+Status CpuProfile::InitProfileInternal() {
+  base::DictionaryValue params;
+  Status statusDebug = client_->SendCommand("Debugger.enable", params);
+  Status statusProfiler = client_->SendCommand("Profiler.enable", params);
+
+  if (statusDebug.IsError())

[klm, 2014/05/10 02:21:57]

Please check the status right after sending the command, otherwise a failure for
Profiler.enable may go unhandled if both fail.

+    return statusDebug;
+  else if (statusProfiler.IsError())

[klm, 2014/05/10 02:21:57]

SendCommand("Debugger.disable") here, to try to clean up on failure as much as
we can?

+    return statusProfiler;
+  else
+    return Status(kOk);
+}
+
+Status CpuProfile::StopProfileInternal() {
+  base::DictionaryValue params;
+  Status statusDebug = client_->SendCommand("Debugger.disable", params);
+  Status statusProfiler = client_->SendCommand("Profiler.disable", params);
+
+  if (statusDebug.IsError())

[klm, 2014/05/10 02:21:57]

Same comments as in InitProfileInternal.

+    return statusDebug;
+  else if (statusProfiler.IsError())
+    return statusProfiler;
+  else
+    return Status(kOk);
+}
+
+Status CpuProfile::StartProfile(scoped_ptr<base::Value>* result) {

[klm, 2014/05/10 02:21:57]

result is unused. Seems to be an artifact of how this is structured in
window_commands.cc, but bottom line is this method conceptually has no return
value, so IMHO it should take no arg, as well as its WebView counterpart, and
window_commands.cc would simply not pass its "value" var -- it remains unchanged
anyway.

+  base::DictionaryValue params;
+  Status statusInit = InitProfileInternal();
+  Status status = client_->SendCommand("Profiler.start", params);
+  if (statusInit.IsError())

[klm, 2014/05/10 02:21:57]

Call StopProfileInternal() here, to clean up?

+        return statusInit;
+
+  return status;
+
+}
+
+Status CpuProfile::EndProfile(scoped_ptr<base::Value>* result) {
+  base::DictionaryValue params;
+  scoped_ptr<base::DictionaryValue> profileResult;
+  Status status = client_->SendCommandAndGetResult(
+      "Profiler.stop", params, &profileResult);
+  Status disableProfileStatus = StopProfileInternal();
+
+  if (disableProfileStatus.IsError()) {
+    return disableProfileStatus;
+  }
+  *result = profileResult.PassAs<base::Value>();
+  return status;
+}
+
+Status CpuProfile::OnEvent(DevToolsClient* client,
+                                  const std::string& method,

[klm, 2014/05/10 02:21:57]

indentation

+                                  const base::DictionaryValue& params) {
+    return Status(kOk);

[klm, 2014/05/10 02:21:57]

indentation

+}