Added trace query code and wired tracing through BrowserProxy so tests can run traces.

chrome/test/automation/browser_proxy.h

 // Copyright (c) 2011 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.
 
 #ifndef CHROME_TEST_AUTOMATION_BROWSER_PROXY_H_
 #define CHROME_TEST_AUTOMATION_BROWSER_PROXY_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 214 matching lines @@
                        std::string* response) WARN_UNUSED_RESULT;
 
   // Gets the load times for all tabs started from the command line.
   // Puts the time of the first tab to start loading into |min_start_time|,
   // the time when loading stopped into |max_stop_time| (should be similar to
   // the delay that WaitForInitialLoads waits for), and a list of all
   // finished timestamps into |stop_times|. Returns true on success.
   bool GetInitialLoadTimes(float* min_start_time, float* max_stop_time,
                            std::vector<float>* stop_times);
 
+  // Begin a trace on the browser instance.
+  // See base/event_trace.h for documentation of included/excluded categories.
+  bool BeginTracing(const std::vector<std::string>& included_categories,
+                    const std::vector<std::string>& excluded_categories);
+
+  // Helper method to begin trace on a single included category filter.
+  // Example: BeginTracing("test_MyTest*");
+  bool BeginTracing(const std::string& included_categories);
+
+  // End trace and collect the trace output as a json string.
+  bool EndTracing(std::string* json_trace_output);
 
  protected:
   virtual ~BrowserProxy() {}
  private:
   DISALLOW_COPY_AND_ASSIGN(BrowserProxy);
 };
 
 #endif  // CHROME_TEST_AUTOMATION_BROWSER_PROXY_H_